Folk religion is more prevalent than you might expect.
Animism, shamanism, and ancestor worship have existed in various forms from the earliest days of Biblical history and these practices are still alive and well. While these religious assumptions are found in tribal cultures, they also pervade many worldwide religions, especially in Asia. This workshop will detail some of the universal beliefs in Folk Religion and provide some practical suggestions for evangelizing and discipling people who live with these assumptions.
Paul G. Hiebert, R. Daniel Shaw, and Tite Tienou. Understanding Folk Religion: A Christian Response to Popular Beliefs and Practices (Grand Rapids: Baker Books)
S. Michael Houdmann, “What does the Bible Say about ancestor worship?” https://www.gotquestions.org/ancestor-worship.html (accessed July 26, 2018).