Well, as far as the first part of your post goes, we both know how each other feels about Paul, Jesus, and the rest of the Bible. So, we can just leave it at that.<quoted text>
On the last part, Paul says so, not Jesus nor the any of the OT.
In fact Jesus says to pray directly to God, not Him.
It goes "Our Father..." not "Dear Jesus..."
As for Moses, many Christinas claim to talk directly to God (IE: Holy Spirit and prayers) and the vast majority claim that the Bible is the perfect instructions from God. Why would it make a difference if God communicates instructions through a vision, a burning bush, a ghost or a book ?
In the OT, God would sometimes speak directly to people, just like I could talk directly to you through the phone or over a cuppa joe. After Jesus returned to Heaven and the Holy Spirit came down, God no longer has spoken directly to anyone.
I guess the difference I was trying to make is that you were talking about a person possibly getting God's instructions wrong through prayer. I think people do feel that they are doing God's will sometimes even when they really aren't, because they misinterpreted whatever it was they received. Moses got his instructions directly from God, so there was no miscommunication. His trouble was his anger!(and that can be most every human's trouble at one time or another)
You have a good evening, and a great weekend,