If you want to go down that road, could you explain to me why the docterine of sola scriptura, private judgement and faith alone was a big "discovery" only after 1500 years! If length of time bothers you, you should really be worried about that. If everybody has the Holy Spirit, surely somebody could have rescued these ideas from the bible a lot sooner, given how important they are.
Sola Scritpura was a return to the church not a deviation from it
How did the early church KNOW that Jesus was the Christ and the apostles? They searched the scriptures to look for prophecy..
The reformation was a return to the practice of the early church..God is immutible..if he said something here he will not change His mind later...check it against the word..Sola Scriptura..