Friendship Gives No Discernment

A personal acquaintance with a famous teacher doesn't give anymore discernment than a third party. In fact, most will defend their "friend" although in grave error, giving the little caveat of not agreeing 100% with what he teaches (as if that's ever possible). What gives discernment is the Spirit of Truth, through training in the Word of Truth. The closer a person is to someone in error, the less inclined they are to confront him. Especially if they are famous.