People who have practiced occult religions for many years are being told that they don't know the first thing about their own religion and its beliefs and practices - and that a bunch of zealots from another religion posing as 'experts' (in a religion they despise/ fear/ oppose and who peddle slander and misinformation about occult religions), are more credible than they are.Non Seqitur. This does not follow.
A sermon preached but yet not practiced will fail to touch the hearts of its listeners and will never bring glory to God rather it will become a loathsome sacrifice that will stink on broken altars. One can be theologically astute but still very immature. One can possibly be biblically literate but still in very much need of wisdom to apply the truth in one's own life.