Despite their claim that the Bible was corrupt, both prophets admonished their followers to adhere to its teachings. An obvious contradiction, this led to selective acceptance of some portions and wholesale rejection of others. As a result, the Bible is accepted by both groups of followers only to the extent that it agrees with their prophet’s own superior revelation.
Are protestants exempt from this process? NO! That is why Jesus tells the seven churches in Revelation to REPENT and go back to your first love.
Except the oral teachings of Moses were the Word of God for 40 years before Moses wrote scrolls, and for centuries before the Prophets.