A definition of Apostasy (Wikipedia)
In Christianity, there are different views about the purpose and the meaning of warnings in the Bible to guard against a falling away from the faith. For anyone struggling with doubts about their own faith or with the doubts of others, this is not merely an armchair discussion, but potentially a question of life and death. Also if loved ones seem to wander from the faith, or if church leaders turn to false teachings even to the point of openly rejecting Christ, being grounded in what the Bible actually says on this subject can be life-saving. To navigate these choppy waters, the approach of the present study series is to compare how Jesus himself and Peter, John and Paul, the most prolific writers among his apostles, addressed this subject in the New Testament.