Christianisation
Introduction
Pagan Festivals
     Christmas
     Easter
     The Birthday of John the Baptist
     All Saint's Day
Biblical Figures
Rituals and Concepts from Other Religions
     Introduction
     Influence of Zoroastrianism?
     Influence of Judaism and Mithraism
     Influence of Hinduism
     The Eucharist/Holy Communion and Neoplatonic Theurgy
     Influence of Egyptian Mysticism
     Triquetra
     Fish Symbol
     Ouroboros
     Obelisk
     Cross
     Rod of Asclepius
Last Updated: 22 May 2014
 
Introduction
Christianisation is the process by which entire populations are converted 'officially' to Christianity has historically also included the practice of converting native pagan practices and culture, pagan religious imagery, pagan sites and the pagan calendar to Christian uses, reinterpreting them as their own.Placing churches over temples of pagan worship was an easy way to maintain loyalty amongst the local population, as they were used to worshipping at certain 'sacred' locations, rather than trying to demolish such temples. Adopting pagan festivals and giving them a Christian interpretation could be either seen as early Christian attempts to appease local populations (or to distract them from their pagan Gods) and incorporate their festivals into the Christian Calendar, or perhaps 'counter festivals' conducted at the same time as pagan festivals, to symoblically oppose the spiritual activity taking place around them, or perhaps as a way to avoid persecutation by 'mingling in' and celebrating when other pagans were celebrating.
It is likely that early converts from Anglo-Saxon paganism to Christianity merely saw Jehovah as just another God that they could worship or include in their array of deities they worshipped, so conversion was not as troublesome as one might imagine; but in the UK for example, resulting in a mish mash of Celtic Christian, Roman Catholic and Anglo-Saxon pagan warrior and honour traditions and values - creating new forms of cultural identity (much like cultural evolution today). One could view this practice as a Catholic Church, already having incorporated its own 'pagan' practices into its structure, further diluting or losing the original Christian message - or merely as a cultural evolution of it.
We should not assume that Christianisation is a thing of the past, and that it was solely conducted by the early Catholic Church. Christian churches have become 'practical' and acknowledge that certain populations simply will not give up their traditional pagan practices and particularly festivals, as they are deeply ingrained in their cultural fabric, and are part of their identity, and they simply carry on these practices in parallel to their Christian faith. In an attempt to make themselves feel better, church leaders try to take over these festivals and rituals and give them nominally Christian references. Does this really mean anything though? For example, in the Philippines, in certain communities, there are fertility festivals that include dancing in the streets. These have been nominally Christianised and now are actually organised by the local Catholic Church! The basic content and spirit is however little different to the original pagan practice. In other parts of Asia for example, animism and ancestor worship occur in parallel to Christian beliefs, and the local churches have often arrived at a compromise, allowing locals to continue their older beliefs and practices whilst singing a few hymns and avoided blantant references to pagan practice, whilst still actually doing it. However, in some communities, such as in aboriginal communities in Australia, aborigines who are converted to Christianity still continue their older pagan practices, but they are now merely ceremonial and the spiritual meaning and knowledge behind them has been lost forever - the rites are merely a case of 'going through the motions'. Whilst not strictly Christianisation, in Africa, missionaries were disturbed by the sexual practices of local Christian converts, and thought them 'unholy' and wished them to only have sex in a certain manner that was considered 'Christian', which is where the expression 'the missionary position' came from.
http://en.wikipedia.org/wiki/Christianization
www.cathar.net/Witness3000/Worship/207_cathars_christmas.html
Christianisation can also be seen in the context of the reasons for conversion, which in Northern Europe, were often for socio-economic reasons, and that becoming a Christian was an opportunity to associate with modern Celtic technology, wealth, prestige, which was in fact the polar opposite situation when the Anglo-Saxons invaded Britain (Christians and 'Britons' (if such a thing existed) associating/identifying themselves with Anglo-Saxons for economic reasons, as they were more likely to get ahead in society if they did). For many such converts, they are unlikely to give up all of their old culture and traditions, and in order to assist in the conversion and retention of conversions, and to provide an incentive, direct replacement or mimmicking of pagan traditions was necessary.
Today, the Christian adoption of early Pagan festivals means for many pagans that much of the essence of these pagan festivals has been preserved and brought into the 20th Century, which they can enjoy and celebrate along with the Christians and non-Christians alike, but knowingly ignoring the Christian parts and focussing on the pagan parts that remain (very strongly!) The pagans are probably wiser to the situation than the Christians who are under the impression for the large part that all these festivals are of Christian origin! So in a sense it is a win-win situation! If you don't consider the perpetuated ignorance of most modern Christians about their own religion and heritage.
One can view Christianisation and adoption of spiritual ideas from other religions in a number of ways. One can view it in a fundamentalist manner, and try to remove all the aspects that you can clearly identify as being pagan from your religion, and depending on how far you want to be, it could adopting a stance similar to Baptist's or Jehovah's Witnesses in certain areas. One could simply be aware of them and just take the more borrowed or comical aspects with a pinch of salt, knowing the historical roots of all the different traditions you are involved with, placing your emphasis, focus and faith elsewhere. One could view it another way and give up on one's religion as it does not seem 'authentic' any more. Or one could acknowledge the spiritual heritage of your religion, and the fact that few if any religions appear out of 'nowhere' and do borrow ideas heavily from other religions, each time creating something different and unique, not necessarily 'better' and all others that you have borrowed from being 'wrong' - perhaps it is a mutation, assimilation or evolution. One could alternatively view the common elements amongst different religions and see the elements of perceived spiritual truth in a number of religions. Or perhaps just put all religions into context and try to differentiate between cultural heritage, appropriation, myth, fantasy and actual concrete spiritual truth free from dogmatic rules, and just understanding and working with the rich variety of spiritual principles available in the world's rich spectrum of religious experience. As long as one is honest with oneself, that is what counts. 
Pagan Festivals
 Christmas:
The Roman festival Saturnalia was converted to Christmas. The Northern European pre-Christian celebration of Yule, in the middle of the Winter Solstice, was Christianised to become Christmas also. 'Jul' in several Scandianavian tongues refers to 'Christmas'. Contrary to the beliefs of many Christians, the date was not picked in December as a likely historical date of birth of Jesus of Nazareth, which was more likely to have occurred some time in the September in 4BC, according to evidence based on astronomical estimates and the actual start of Augustus rule under the name Octavian 4 years earlier. There are several theories, most assuming Jupiter to be the 'star' in question, in rare retrograde motion (changing direction across the sky over a period of weeks) in Pisces. However, other theorists base their assumptions on a date of 1BC, on account of a transcription printing error in the Josephus' manuscript, which arrives at a date of 25th December - this view is not widely accepted..http://users.aristotle.net/~bhuie/birthday.htm
http://en.wikipedia.org/wiki/Yule
Santa Claus, a.k.a. Santa, Saint Nicholas, Father Christmas or Kris Kringle is a historical, legendary, and mythical folklore figure who, in the context of Western cultures, is the bringer of gifts on Christmas Eve or Christmas Day, or on his feast day, 6th December. The legend may derive fromhagiographical tales of the historical figure, Saint Nicholas.
http://en.wikipedia.org/wiki/Santa_claus
This date or celebration of the non-canonised saint Nicholas has been combined with the 'birthday' of Jesus, on the 24th or 25th December (depending on location), as part of the modern Christmas Tradition. Are we confusing Nicholas with Jesus and with someone dressed in red and with a white beard who uses 'magic' to travel through the sky and give presents to 'good children'? The tradition is somewhat confused as 'Santa Claus' does all the giving, with the children just 'receiving'. Isn't it about giving?! It is held that there are many parallels between the Germanic pagan god Odin and Santa Claus in appearance.
The tradition of the Christmas Tree or Yule Tree dates back to Pre-Christian Europe, where the keeping of an evergreen tree inside the house during the winter was a common site. The tradition derives mainly from the patron trees of Germanic pagan tribes, e.g. Irminsul, Thor's Oak and the figurative Yggdrasil. Saint Boniface in Germany is credited with the invention of the Christmas Tree with a Christian significance, when he chopped down Thor's Oak in a stage managed confrontation, using the Oak instead as a Christian symbol. Throughout history, evergreen plants have been used for decoration in the winter, from laurel, mistle or conifer, and trees had a cultural importance like the maypole, the Saturnalia or the Gerichtslinde. Other notable traditions in relation to Christmas have also been derived from Germanic pagan practices, including the Yule log, Christmas ham, Yule Goat, stuffing stockings, elements of Santa Claus and his nocturnal ride through the sky, and surviving elements of Pre-Christian Alpine traditions.
http://en.wikipedia.org/wiki/Christmas_tree
The concept of Christmas is particularly confused, because on the one hand you have the birth of Jesus in the desert, and on the other hand you have winter imagery of snowscapes, snowmen, and the 'veneration' of a Tree in the home, clearly a tradition of pagan origin; and then you have Father Christmas! And also the modern commercial concepts of consumerism and children receiving/expecting/demanding expensive presents and toys. What exactly does Christmas represent? An excuse to feast and get drunk, in the pagan tradition (a Pagan Alcoholiday!)? A time of prayer, austerity and celebrating the birth of Jesus? A time of good will to all mankind? A time for families to get together, a celebration of the family (which Jesus was quite clear that he was opposed to!) A time to sit on one's 'butt' and watch television and James Bond movies? Many people assume that eating turkey and a 'Christmas lunch' or 'dinner' is traditional for all Christians, but in the West Indies, the tradition is to eat Oranges! A far cry from the Northern European pagan-influenced festivities.
Is the whole concept of celebrating one's birthday pagan? One could argue that it is as it is a celebration of a specific day of the year, according to the part of the season one was born in. Jehovah's Witnesses do not celebrate birthdays, nor Halloween, Christmas or Easter as they are considered to be pagan. http://en.wikipedia.org/wiki/Jehovah's_Witnesses
However, there is no Biblical evidence or guidance on the issue of birthdays, so whether it is or not is anyone's guess and up to the individual as to whether they regard the concept as ridiculous or not. Clearly the authors of the various books of the Bible expected readers to use their brains a little and to think for themselves.
http://jesus-messiah.com/html/birthdays.html
Clearly no one likes the sudden increase in age on one day of the year and kidding oneself that one is not older the other 364 days of the year because one's age number is the same! But everyone likes presents and bonding with friends and family on one's birthday. Surely one should celebrate one's birth, i.e. life, every day? Food for thought. 
Easter:
The name of Eostre converted to English "Easter" to identify the Paschal festival.www.religioustolerance.org/easter1.htm
People often assume that Easter represents the resurrection of Jesus Christ, and that the egg represents the stone that blocked Jesus' tomb, that was moved as Jesus was resurrected. However, just how is a rabbit connected with an egg? Clearly rabbits do not lay eggs as they are mammals! The imagery of hares/rabbits and eggs in fact derives again from pagan traditions.
http://altreligion.about.com/cs/alchemy/a/mpreviss.htm
http://en.wikipedia.org/wiki/Walpurgisnacht
http://en.wikipedia.org/wiki/May_day 
Birthday of John the Baptist:
The celebration of Midsummer Day (the summer solstice) was converted to the birthday feast of John the Baptist. All Saints' Day:
The celebrations of the Roman Feast of the Lemures and of Celtic festival Samhain combined and transferred to the eve of All Saints' Day a.k.a. Halloween.http://en.wikipedia.org/wiki/All_Saints_Day
http://en.wikipedia.org/wiki/Halloween#Religious_perspectives
http://en.wikipedia.org/wiki/Feast_of_the_Lemures
http://en.wikipedia.org/wiki/Samhain
One may choose to take the dates and the celebrations of the above Christianised festivals with a pinch of salt, as they are perhaps slightly pantomime in nature and today highly commercialised and more about children, and consumer products and eating chocolate, receiving presents and pictures of a dude with a red hood and a beard than the actual spiritual meaning. However, this is not to say that one should not celebrate the Christian religious meaning behind the festivals, and indeed that one should not do so on other dates or indeed every day! Although it feels better when celebrating something jointly with a large number of other people, one does not necessarily have to stick to arbitrary pagan celebration dates. 
Reinterpretation of Biblical Figures
Biblical figures such as Mary, the mother of Christ, and Satan, could be seen to have been given non-Biblical interpretations after the Canonical Gospels were written and finalised. The veneration of Mary, and the image of the mother with child could be compared with the pagan and indeed neo-pagan concepts of Mother Earth and the Sun God. Please see the section on The Devil page. Christianised Rituals and Religious Concepts
 Introduction:
One could also argue that early Christianity borrowed heavily from other religions, but whether the concepts were ideas that happened to be common to a number of different faiths or whether they were plagiarised is a matter of debate and clearly must be evaluated on a case by case basis. Whether early Christians were influenced by such ideas and concepts and incorporated them into their own faith (being reluctant to give up the ideas of their old religions), or whether they were later traditions or refinements that coincided with other religions, or whether these were concepts taught directly by Jesus, but not recorded, is a matter of debate. Most of the concepts and festivals that are considered 'plagiarised' or 'Christianised' appear to derive from the time between the 1st and 4th Centuries AD.http://en.wikipedia.org/wiki/Christianization#Ritual
Most religions have more in common that we would like to admit. An example in case in Christianity and Islam. Muslims regard Jesus as a prophet, but are waiting for his return to earth, just like Christians. Many Christians however regard Judaism as being closer to Christianity and fear Islam, whereas many Jews regard Jesus as a fraud and as a heretic. In many ways, Islam is closer to Christianity than Judaism. In a sense, it is useful to understand Judaism to understand Christianity, especially as they share the OT (i.e. Tora). Christianity shares many of the teachings of Buddhism also, but there are of course differences. Islam acquired the tradition of humility and surrender through postration in prayer from Egyptian Coptic Christianity. 
Influence of Zoroastrianism?
There are a number of parallels between some of the core concepts of Christianity and Zoroastrianism. Zoroastrianism, examined above, introduced concepts of Heaven and Hell, an independent force of evil on the earth, the concept of a saviour born of a virgin birth, judgement at death and also the Final Judgement. Zoroastrianism as a religion however was very much racially and geographically focussed, whereas Christianity made a break from Judaism as the religion for the Gentiles as well as the Jews. One can speculate to what extent the New Testament and canonical Gospels were influenced by Zoroastrianism, and to what extent they 'sexed up' the story of Jesus and the new concepts (above) that did not exist in Judaism. One could also conclude that it was either simply a coincidence, or a partial acknowledgement/realisation of (a version of) spiritual truth, before the time of Christ. The virgin birth story would clearly have to have been a coincidence if one is to believe this - or it was directly copied. Zoroastrianism does not encourage conversion, but holds that other religions offer an equally valid spiritual truth. This is not the case with Christianity, which held the exact opposite philosophy in this regard.Please click here to read an article on how Zoroastrianism is seen to have influenced Christianity and Islam.
www.gotquestions.org/Jesus-Mithra-Christianity-Zoroastrianism.html
http://www.pyracantha.com/zjc3.html
Whilst not a direct influence on the religion of Christianity, Zoroastrianism is thought to have a place in the NT story of Jesus. The wise men or magi mentioned in the Gospel of Matthew were thought to be Zoroastrian priests or astrologers, travelling from Persia in the East towards Israel, driven on the star of Bethlehem. There is no mention of there being three Magi or wise men, but it has often been assumed or depicted like this, on account of the reference to three gifts to the newborn Jesus.
http://en.wikipedia.org/wiki/Magii
In biblical times, there was no separation of astronomy and astrology, and science and religion, as we know them today, but they were one and the same. All famous historical astronomers were astrologers and often priests. They combined the scientific study of the stars and the visible universe with 'non-scientific' predictions based on the movement of the planets within (i.e. in front of) different constellations (corresponding to astrological symbols and representations of animals).
http://en.wikipedia.org/wiki/Astrology
The three Magi are thought to have been Zoroastrian astrologers. In the stars, they likely saw a symbolic representation of the birth of a new ruler or king of Israel, and the star led them to Bethlehem. The magi played an important part in the story of the birth of Jesus. They were adding weight to the notion of Jesus being the Messiah and the King of the Jews, but also in that although they alerted Herod to the star, which he had clearly not noticed himself, and Bethlehem being the birthplace, they were warned by God in a dream not to return to Herod to reveal the exact location of Jesus and returned home by another route, avoiding Herod. So in short, we have several Zoroastrian astrologers who were believers, and who did not give up their astrology disciplines or Zoroastrian religion, but seemed to merely adopt/integrate a belief in Jesus. Astrology therefore has an important part to play in the Bible. God did not denounce their astrology or existing beliefs. God did not choose to communicate with many people in the Bible in a dream, so clearly the magi were held in high regard and were special or chosen. So whilst, Christians denounce Astrology as being pagan, God has no problems communicating with Persian astrologers who came to worship the newborn Jesus. This is not quite the same as the modern Christian church's view of astrology. I am not necessarily promoting astrology, but it should be seen in its right context. Perhaps now that astrology is a separate discipline to astronomy, we can discard astrology as being historically outdated, but if the wise men were merely astronomers, and had no belief in the meaning of the observed star, they would never have come to Bethlehem nor been spoken to by God. So it is not so clear cut. Did astrology have any part to play in early Christianity? Much like other 'scientific' views of the day were a little superstitious? 
Influence of Egyptian Mysticism
Various examples below are examined in terms of cultural influence of Christian traditions from ancient Egyptian religion and mysticism, including, the symbol of the Cross, the Obelisk and the practice of saying 'Amen' at the end of prayers. Indeed, one could perhaps interpret Abrahamic religions as an evolution of pagan Sun God worship, dating back to early Egyptian and Hindu religion. In the 18th Dynasty in Ancient Egypt, Akhenaten changed the polytheistic religion of Egypt to a monotheistic one, of Aten worship. This is arguably the first true monotheism in religion history. Perhaps Moses was inspired by the power of this monotheism, but wished to change some of the basic precepts of the relationship with that deity, to create a new type of religion that was Jewish and yet completely different, which was ultimately to inspired Christianity. The metaphor of 'light' is very prevalent in Christian imagery and also in Biblical references in the New Testament. Of course, this could just be a coincidence and is one interpretation of many.http://en.wikipedia.org/wiki/Solar_deity
Here we shall examine the origin of the crucifixion and resurrection myth. There are parallels between Christ's crucifixion and resurrection and the fate of Osiris. Osiris was eldest son of the Earth God Geb. Osiris was the God of the Afterlife, the underworld and the dead in ancient Egyptian mysticism. Osiris was murdered by his brother Set, and his body set up in a tree (c/f a wooden cross) and was later resurrected.
http://en.wikipedia.org/wiki/Osiris
http://knol.google.com/k/a-pagan-myth# 
Influence of Judaism and Mithraism?
Mithraism was an initiatory order in the 1st to 4th Century Roman Empire, drawing on Zoroastrianism and perhaps Manichaeism (or perhaps it was the other way around).http://en.wikipedia.org/wiki/Mithraism 
Influence of Hinduism?
As discussed below, the concept of the Trinity was already present in other religions, such as in Hinduism (Brahma, Vishnu and Shiva), Babylonian mythology (Anu, Bel and Ena) and Roman mythology (the trinity of Jupiter, Juno and Minerva - ignoring the other Gods).Hinduism perhaps influenced Christianity in other ways, such as the use of Angels (Devas - "Beings of Light") and Archangels (Mahadevas - "Great Beings of Light"). In Hinduism, Mahadevas are worshipped, as deities, whereas Devas are just thanked for their good works. Angels in Christianity and Judaism appear to carry out the will of God, either to exact vengeance or to pass on a positive message from God to specified individuals, for example.
http://en.wikipedia.org/wiki/Angels
Some say that Krishna, the 8th incarnation of the deity Vishnu, was a carpenter, but there is no scriptural evidence to my knowledge to base this belief upon. Krishna was born of a virgin birth, of the Virgin Devaki, who was impregnated with the hairs from the head of Vishnu placed into her womb. Some say that this myth relates very closely to that of Jesus. However, there are of course differences in context and narrative, as Krisha was merely a incarnation in a long line of incarnations, whereas Jesus came only once (and is said to return for a second time only at the 'end of days'). Jesus was also prophesized in the Old Testament a thousand years before his birth, depending on how you interpret the scriptures, whereas Krishna was not. Krisha's mother was impregnated with 'hairs' from Krisha whereas Jesus' mother was impregnated with the Holy Spirit. However, the similarities are quite striking. If the latter is correct, are later renditions, refinements or culture/racial-specific versions of the same or similar story indicative or a primal truth or just appropriations of other traditions? For example, if a prophet, son of God or 'Aeon' was born of a virgin birth, were they all born of a virgin birth? For each prophet/holy man to be born of a virgin birth seems rather far fetched, so either one must be correct and the others are 'copies', or they are all based on ancient myths perhaps. There are of course many different possible explanations that one might consider.
www.blackapologetics.com/bamanswerantiquity.html
Were the above merely influence, a coincidence or an acknowledgement of a spiritual reality derived thousands of years before? Or perhaps a reflection of the rivalry and/or influence on a given religion by those that went before it, perhaps to 'sex up' it's own spiritual texts and traditions from historical figures, or to try to convert followers of other related religions by including elements of their religious traditions within it (by making them feeling comfortable or at home with Christianity) - to ensure maximum conversions. Or perhaps these elements became adopted as the message of Jesus was spread throughout Asia as it mixed with indigenous religious practices and ideas, just as occurred in modern times with the spread of Christianity across the globe, where the church sanctions local mixing of indigenous pagan/animistic/spiritualist practices and fertility rites but branded as nominally Christian to appease the locals and so they do not lose touch with their old traditions that they love. 
The Eucharist/Holy Communion and Theurgy:
The Eucharist, or Holy Communion is the ceremony of the breaking of bread and sipping of wine, taking in the body of Christ and the blood of Christ, as in the Last Supper. It could in some respects be classed as a form of Theurgy, a symbolic ritual where one takes in 'God' into one's body in order to elevate oneself spiritually and become 'more divine'. The Holy Communion as a practice suggested by Jesus to be taken up by the disciples is described by Paul in the First Epistle to the Corinthians (c 54-55). It is described as something Jesus did but not something Jesus instructed his disciples to do in the Gospels of Matthew, Mark and Luke. John's Gospel does not mention it at all. I wonder why Holy Communion often occurs with congregations looking so bored, unemotional or being so quiet, and often performed using 'mini-glasses' and 'mini-wafers' so that those of weak faith need not have their faith challenged by their weak, neurotic hygiene issues. In addition, do congregation members look ecstatic or enlightened after taking Communion? Not in my experience, in Baptist, Anglican and Evangelical churches. Is there really any need for it? In my opinion it all seems rather ridiculous - not unlike an overly ceremonial and pompous magic ritual. Unless the spirit of the Communion is there, the passion and fire, then surely it's not Communion and it shouldn't be taking place.http://en.wikipedia.org/wiki/Holy_Communion
Theurgy derives from Neoplatonism, the philosophy and religion so despised by many Christian Churches as heretical.
http://en.wikipedia.org/wiki/Theurgy
Theurgy in Judaism can be found in The Tree of Life in the Kabbalah.
According to several secular scholars, the fact that even early Christian church fathers admitted that the other religions used these rituals, and that they admitted the other religions used them first, suggests that Christianity adopted them from these sources, and the biblical narrative was invented later to justify Christian usage. However, it could also be argued that the biblical narrative refers to the practices as they were known in Judaism, while the forms in traditional Christianity were taken from other religious sources.'
The use of bathing in Judaism as a form of ritual cleansing, the Mikvah, is slightly different to the meaning of Baptism in Christianity. The Essenes, a Pre-Christian Jewish Sect, bathed several times a day as part of their ritual purification.
http://en.wikipedia.org/wiki/Mikvah
The concepts of baptism were present in Pre-Christian Egyptian pagan traditions (e.g. Horus), and it has been argued that Coptic Christianity absorbed such traditions (assuming the Canonical Gospels were altered later to reflect this) or perhaps these traditions influenced the actual characters (John the Baptist, Jesus) in the Bible in the time of Jesus.
www.religioustolerance.org/chr_jcpa5.htm
www.mystae.com/restricted/reflections/messiah/pagan.html 
Triquetra and NKJV Bible:
The Bible has been translated into a number of different versions since the 1611 Bible, e.g. New American Standard Version, New International Version, Revised Standard Version, and Good News Bible are amongst the most popular. The New King James Bible is a version of the King James Bible translation reputed using more modern English. There are various arguments for and against this version as it makes rather unusual changes. My personal opinion is that if you want to read the KJV, then read the KJV and not the NKJV. If you want to read a modern Bible, then read a modern Bible. Please see the section below on Christianisation for more information.The NKJV uses the Triqueta on the cover. It is claimed that it is a Christian symbol representing the Trinity.
Exodus 20:4 (KJV) states: 'Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth'
Let us consider the origin of the Triquetra - it predates Christianity and is likely to have been a Celtic symbol of the Goddess, and in the North of Europe, a symbol of the deity Odin. The Celts used the symbol to represent the triplicities of the mind, body and soul as well as the earth, sea and sky. No tripartite goddess has ever been identified with the symbol. It is used by Wiccans and Neopagans today as aspects of the Triple Goddess (Hecate) - the three phases of the moon - waxing, full or waning - and also maid, mother and the old crone. In a Christian context, the Triquetra is most commonly a symbol of the Holy Trinity i.e. Father, son and Holy spirit first used by the Celtic Christian Church - occasionally represented by 3 interlocking fish.
http://altreligion.about.com/od/symbols/p/Triquetra.htm
Certain Baptist Christians may make a fuss about how the Triquetra is used on the NKJV Bible, but Christianity has been appropriating symbols from other religions - not that there is necessarily anything wrong with that - so why focus on the Triquetra and not the other symbols for instance. Protestantism in general has sought to eliminate some of the old Catholic symbolism and Roman practices from its repertoire but still honours old pagan festivals etc. so drawing the line here, so vehemently, seems rather arbitrary in my opinion.
www.av1611.org/nkjv.html
www.letgodbetrue.com/bible/scripture/new-king-james-version.htm 
Fish symbol:
The fish symbol, or Ichthys, used by early Christians and in modern times, by Evangelical Christians has its roots in pagan religion. Is this really a suitable symbol for modern evangelical Christians to use? Why do they indeed need a symbol? If they are not to use the Cross, then why bother using any symbol at all? The fish symbol is often jokingly referred to as the 'Jesus fish'.
www.religioustolerance.org/chr_symb.htm
www.atheists.org/christianity/fish.html
Counter arguments from a Christian perspective can be found at the link below. These rely on the idea that just because pre-Christian pagan traditions 'may' have used the fish to represent various concepts of fertility etc., this does not mean that its use automatically means that it is non-Christian. However, adherents of this theory probably would like to imply that there is no Christianisation whatsoever, or at least not draw attention to it!
www.tektonics.org/copycat/fishsymbol.html
http://en.wikipedia.org/wiki/Ichthys 
Ouroboros:
Above art by Theodoros Pelecanos, in the alchemical text Synosius (1478). This depicts the symbol 'Ouroboros', the Serpent eating its Tail, has been used to represent many different concepts throughout history, mainly cyclicality, divine life, infinity and unity. It is sometimes used to represent the concept of Reincarnation.
http://en.wikipedia.org/wiki/Ouroboros
The Ouroboros has also appeared in Norse mythology, Hinduism, Alchemy, Aztec religion and also in Gnosticism.
It is reputed that the Ouroboros was a 'secret code' used to demarc early Christian graves. 
Obelisk:
Obelisks were a prominent part of the architecture of the ancient Egyptians, who placed them in pairs at the entrance of temples. The obelisk symbolized the sun god Ra, or Re as some know him, and during the brief religious reformation of Akhenaten was said to be a petrified ray of the Aten, the sundisk. It was also thought that the god existed within the structure.http://en.wikipedia.org/wiki/Obelisk
The Vatican moved the giant Obelisk from Rome to a position in front of the main building at St Peter's Square in the 16th Century AD. It had originally been excavated in Egypt in the 13th Century BC, brought to Rome in the 1st Century AD by the pagan Roman rulers. The Obelisk has a nominal cruficix on the top. This is a classical case of Christianisation! What this has to do with St Peter or Christianity is not clear! It is not the first time that Egyptian religious symbolism has appeared in a Catholic context.
www.lindahall.org/events_exhib/exhibit/exhibits/civil/vatican.shtml
The use of ancient Eyptian symbols in a political/religiouscontext is discussed elsewhere on this site on the Bavarian Illuminati page. 
Cross:
Many people assume that the cross is of Christian origin, and that other uses of the cross are copies of Christianity's symbols and therefore attempts to mock or distort Christian symbolism. However, the cross symbol probably originates from Ancient Babylon and the corresponding worship of the sun gods Mithra and Tammuz, where usage of the cross was widespread in an almost identical form. In ancient Egypt a variation of the cross is seen in the Ankh symbol.www.albatrus.org/english/religions/pagan/origin_of_cross.htm
The Emperor Constantine, the former pagan sun worshipper, was reputed to have envisaged the cross in front of the sun, in a dream according to Lactantius, and in the heavens/sky just before the battle at Milvian Bridge, according to Eusebius (depicted below). This was Constantine's Cross, called the Chi Rho, as opposed to the cross we see today in predominant use with the corpse of Jesus nailed to it.
The Chi Rho is the earliest of the Cruciform symbols used by Christians, formed by superimposing the first two letters of the word 'Christ' in Greek, Chi = ch, and rho = r. It is not technically a cross but invokes the crucifixion of Jesus as well as symbolising the status of Jesus as the Christ (later with the letters Alpha and Omega on either side of the Chi Rho. The two bar cross was adopted afterwards, as a literal crucifix.
http://atheism.about.com/od/constantinethegreat/ig/Constantine-Emperor-Rome/Constantine-Vision-Cross-Sky.htm
Other parallels to the unification of Sun God worship with Christianity (perhaps to ease uptake or because Constantine was still very fond of his old religion) include the declaration of the Roman Sun Day to be the Christian Sabbath (not Saturday like in Judaism) of the Nicene Creed of the First Council of Nicene in 325 AD.
http://en.wikipedia.org/wiki/Sunday
The adoption of the cross was arguably a form of idolatry and focussing on the Pauline emphasis of the resurrection of Christ as being at the forefront of Jesus' message and purpose rather than what he actually said about the kingdom of heaven and everything else. The Apostles certainly never walked around wearing Crosses or would ever have conceived of doing so! Imagine that.
Some variants on the cross can be seen at the links below.
www.nazarite.net/satanic-symbols.html
http://en.wikipedia.org/wiki/Cross
The cross's pagan origins are displayed in the 19th century secret society, the Hermetic Order of the Golden Dawn, whose Rosy Cross incorporates other magical elements. Some Christians confuse the Christian Cross with the Ankh, the ancient Egyptian symbol, and I even heard of one Christian wearing one, thinking it was a crucifixion symbol. 
Rod of Asclepius:
Source: Catherine Munro
The Rod of Asclepius is an ancient Greek symbol for astrology and also medicine and healing. It is represented by a snake entwined around a staff. In Greek mythology it is the staff of Asclepius, the son of Apollo, who was a practitioner of medicine.
http://en.wikipedia.org/wiki/Rod_of_Asclepius
The symbol of the staff with a serpent wrapped around it also appears in the Old Testament in the Book of Numbers 21:6. Here it is known as the Nehushtan, a copper snake on a pole, depicted above in Michaelangelo Buonarroti's 1508 painting on the ceiling of the Sistine Chapel.
Then the LORD sent poisonous serpents among the people, and they bit the people, so that many Israelites died. The people came to Moses and said, "We have sinned by speaking against the LORD and against you; pray to the LORD to take away the serpents from us." So Moses prayed for the people. And the LORD said to Moses, "Make a poisonous serpent, and set it on a pole; and everyone who is bitten shall look at it and live." So Moses made a serpent of bronze, and put it upon a pole; and whenever a serpent bit someone, that person would look at the serpent of bronze and live.
http://en.wikipedia.org/wiki/Nehushtan
This is likely an example of early Jewish mythology being inspired by this tale from Greek mythology, and being appropriated and taken into a Judaic context.
The symbol has been used as a medical symbol for the last few hundred years, representing 'medicine', appearing on ambulances and medical alert tags. There has been some confusion between the Rod of Asclepius and the Caduceus, a different ancient Greek symbol with two snakes on it, and the Caduceus has been adopted by many medical bodies as their symbol since the 19th Century, despite the symbol having no medical context whatsoever! The Caduceus is the symbolic representation of Hermes, the God of travellers, thieves, orators, poets, sports and athletics, weights and measures, invention and commerce.