Pretty easy to say in 2013. Not so easy in 213. All of the heretics had Scripture to back their heresy. They still do.
You've surely read some Greek philosophy, maybe a bit of Philo, so if you agree please tell me what Greek philosophy would have been a help c.213 in understanding Matthew 6:5-16 or John chapter 17.
The true “heretics” have never been satisfied with the Scriptures, hence the Gnostics, the pseudo Gospels and reliance on pagan philosophies and traditions of men. Both Jesus and Paul warned of the inroads that were and would be made so why are their words on the subject so “blithely dismissed”?
That the backwardness of it...Just as this piece points out, Catholics rely on philosophers to understand and teach the words of God...
The words of God were kept hidden from the lay people and the lesser of the priesthood of the early Catholic religion so they couldn't see what God said...
And those that did/do get their hands on some scripture and believed it, you call heretics...The Apostle Paul had the same problem...
Act 24:14 But this I confess unto thee, that after the way which they call heresy, so worship I the God of my fathers, believing all things which are written in the law and in the prophets: