As some have already said, the term "cult" often gets mis-used to mean we do not agree with their teachings or practices.
That's right. A cult is a religious group that denies or conflicts with the Bible-based fundamentals of the Christian faith (hope I explained that right). Christian churches that are merely legalistic in nature are not cults if their doctrine holds to these fundamentals, even if they do have other ideas/interpretations regarding theology, rituals, works, and meanings of certain Scriptures. They can be mistaken for cults due to their, what-you-call, "exclusive" nature, but I know there is a difference because these conflicts lie in the
secondary issues on which Christians can and will disagree (and Romans 14 touches on that in great lengths). I have heard some people refer to the so-called King James Only movement as a "cult". It is not a cult at all; they're just a bit outlandish to me in that some in the movement have implied that others who disagree are "less holy", "blind" to the "true knowledge" of God's Word, or don't really care about pleasing God. However, that's a topic for another time.
But cults are not about these secondary issues; they come right out and deny the Biblical basics of the faith. The
primary truths about Jesus's divinity, virgin birth, crucifixion, and resurrection. That Jesus is the only way to come to Father God, and only He is to be worshiped. If a church just happens to be legalistic in nature, but adheres to all of that, then they are not cults (although some cults can be legalistic, too.)
Like I said, I haven't found anything that would make me believe that Bill Gothard and his group would be a cult. As far as I know, his statement of faith is based totally on God's Word. I'll have to study a little more about him. He is certainly an intriguing figure in the realm of Christianity, I'll say that much.
Yeah, I'm probably "preaching to the choir", but that's the best explanation I can give of the different between a cult and a legalistic church. I just hope I didn't add more confusion to the topic than what's already there (I don't think I'm the greatest at explaining things most of the time).