Syncretism means the fusion of two or more thought systems, and can be applied to philosophy, politics, and religion. Religious syncretism usually involves the addition of a few essential parts of one religion to a dominant religion, resulting in a new religious system. It is important to distinguish syncretism from contextualization. Changing the way a religion is described or the way a particular rite is practiced to make it understandable to a culture is not syncretistic, since it does not add a foreign religious belief to the system, nor does it actually change the original belief.
What is syncretism? How do some people try to blend religious or other thought systems?
Syncretism has been a serious issue throughout Christian history. Missionaries and indigenous Christians have struggled against both the addition of local traditions or religious tendencies to biblical doctrine, and against the simple addition of certain pieces of Christianity to an indigenous population's religion. The former happened extensively in South America, particularly during Spanish colonization, when some of the animistic and superstitious practices inherent to the tribal cultures were added to the colonists' imported religion. On the other hand, those who work to spread the Gospel to Hindus and similar religions often have a difficult time explaining why Jesus Christ is more than another deity to be added to their polytheistic belief system (this is explained here).
Christianity is by no means the only religion to deal with the problem of syncretism. Islam is often combined with folk religions in the Middle East. Systems like New Age are easily applied to many religions, and a practically infinite number of combinations of religions can be made into cults and sects.
Syncretism is a very unfortunate phenomenon, particularly within Christianity, for it inevitably changes the Gospel, the heart of our understanding of God and His desire for our salvation. Christianity's basic tenets must not be changed, for Jesus made it very clear that salvation and relationship with God only come through Him: "I am the way, and the truth, and the life. No one comes to the Father except through me" (John 14:6).
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