Over time many institutional mainstream churches have adopted cultic beliefs without actually knowing it. Yet, they view themselves scripturally and historically solid by comparison with extreme and harmful cults.Tolerance for biblically unqualified church leaders starts to become acceptable; historic values, practices and once-extensive doctrinal statements become watered down in favor of cultural relevance and inclusivity. Scripture is over-ridden by men and women of letters who are elevated by congregants, and spiritual and intellectual blindness often starts to infect churches.
Some pastors experience epiphanies whereby they realize certain things they have been taught and believe are wrong. Still, they will not change because that would be career suicide. So they stay with the institution and continue to serve its needs, all-thewhile becoming hardened to certain truths that they once may have realized.
Congregants feel compelled to defend their pastor, his teachings, and the organization, believing that is their Christian duty, meanwhile heaping error upon error. In time, still holding core Christian values and basic doctrines, the church slowly adopts cultic elements.
When churches begin to serve the institution and denomination more than scripture and Christ, it sets the stage for a return to bondage in Babylon.
 1 Timothy 3:1-7
 See my book, “Great Apostasy,” chapter 2