From a web-only resource at Mission Frontiers, What Does Syncretism Mean?, by a Native American, Casey Church (Hole in the Clouds):
I am suggesting that, in the light of the writings of Alan Tippett, in Christopaganism or Indigenous Christianity, edited by Tetsunao Yamamori and Charles Tabor (1975), Dean Flemming, Contextualization in the New Testament, Patterns for Theology and Mission (2005), Scott Moreau, Evangelical Dictionary of World Missions (2000), Eunice Irwin, “The Status of Syncretism in Missiological Studies and a Modest Proposal for the 21st Century From the Perspective of Fourth World Peoples” (2006, Unpublished Paper) and Charles Stewart and Rosalind Shaw, Syncretism/Anti-Syncretism, The Politics of Religious Synthesis (1994), a viable, biblically valid view would be that syncretism is a normative stage in the process of spiritual and cultural transformation, not a fixed end-state (though it could be). Our current evangelical definitions have tended to view syncretism in terms of being a final product – static – the result of people mixing good and evil beliefs or practices.
Charles Kraft notes the question faced by Christian witnesses is, however, “whether any given undesirable state is but a step in a continuing process or whether the changes have virtually come to an end and the people are settled in their present beliefs and behavior” (Kraft 1996, 376). Is someone simply passing through on his or her journey, or have they decided to settle in and dwell there? Another consideration is that syncretism just means mixing, so the church is highly syncretistic and rightly so, since the gospel always gets inside culture (parable of the yeast and the dough, parable of the mustard seed, parable of the wheat and the tares). So, the questions are: is this a step or the end product? And, is this a kind of mixing that respects God and culture, or the kind of mixing that eliminates either God (what most people mean by syncretism) or culture (what the conservatives end up doing).
Peter van der Veer suggests that the term syncretism refers to a “politics of difference and identity” and that as such the notion of power is crucial in its understanding. At stake is the power to identify true religion and to authorize some practices as ‘truthful’ and others as ‘false’ (van der Veer 1994, 196). Syncretism came to be used by defenders of “the true faith” as a protection against illicit contamination - a sign of religious decadence, betrayal of principles, or the corruption of the truth. What it attempted to do was establish itself as the single source of authentication (van der Veer 1996, 197).
True conversion, becoming conformed to the person of Jesus, is a gradual process of socio-cultural change or acculturation. It is not an evenly paced change, but varied, uneven, erratic, messy, unpredictable and fluctuating.
There does exist a legitimate concern about syncretism that I refer to as “negative syncretism,” that is, the rejection of the centrality of the Biblical, historical Jesus Christ as savior, redeemer, reconciler, sacrifice, provider, healer, intercessor, mediator, atoner, protector, etc. The rejection stems from an assumption that other religious beliefs / spiritual practices are equally dynamic in fulfilling God’s intended purposes for creation through Jesus. This syncretism flows out of uncritical religious pluralism. Because of this erroneous or misdirected assumption, negative syncretism is a blending or mixing of traditional non-Biblical religious beliefs with Christian faith, producing a differing hybridized and truncated gospel. To equate these beliefs as synonymous is syncretism because it takes away from the real message of communion - the redemptive death and resurrection of Christ.
Syncretism is problematic when it directs one's allegiance to other than Jesus Christ by reason of a person's participation in a new religious system - one created from the blend, which dilutes or redirects faith to someone/something other than Christ. Kraft (referencing the work of Alan Tippett) refers to this condition as “Christopagan Syncretism” (1996, 376). This occurs when people hear and adopt the stories of the bible in the foreign forms of the missionary, but interpret them in local ways, which might result in, as Kraft notes, “anything but Christianity” (1996, 376).
And so it is often today that church leaders who are “in control” in their respective positions of church polity often interpret new movements as in contradiction to “authentic” Christian faith, because it often flows outside the confines of their culturally informed and shaped traditions of Christianity; this is certainly true in Native ministry throughout North America. When rethinking and defining cultural adaptation as normative, an honest threatening fear of syncretism often surfaces, not because of a mistrust of the Word, but because of the long arm of mission history (Gilliland 1989,13).
There is a trend to define syncretism as simply mixing. So all churches and Christians would be “syncretistic” to a varying degree. Abu Daoud calls this “organic syncretism.” But, in my opinion, I think we would be better would refer to this “mixing” as contextualization or enculturation. Defining “syncretism” in such a broad way “results in a term that looses its analytic meaning” (Moreau, p. 924). What this article defines above as “negative syncretism” is how we should plainly define “syncretism.”
The gospel is cultural permeable by God’s design. We cannot articulate the gospel or embody Biblical faith in a way that transcends culture (Carson). The incarnation shows us how God can “mix” with humanity and be without sin, still holy and ultimate and perfect while nevertheless fully human at the same time. I don’t think it makes linguistic sense to say Jesus was syncretistic.
Of course, we need to watch out for “negative syncretism,” i.e. “syncretism” in our ministries. But inevitably, Biblical faith and the gospel will always be contextualized. This is also called contextualization without compromise, done both by indigenous believers and ex-pats, either consciously or unconsciously. Over-contextualization and under-contextualization can both lead to (negative) syncretism. Local and imported cultures can each dilute the essential elements of the gospel.
Syncretism is akin to idolatry. We all have our own idols. But we shouldn’t, of course. God is jealous. However, the process of avoiding or eradicating syncretism is extremely complicated. I can’t even figure it out in my own life; I need other believers, even ones from other cultures, as well as a correctly interpreted Bible illuminated by the Holy Spirit to see my fake gods. But indigenous believers will actually be much better at spotting idolatry in their beliefs and practices than outsiders. Expatriates shouldn’t be the only ones who identify something as syncretistic.