So, when Paul wrote all of those letters he was God? Or was he Paul?
Paul of course. The infinite comes to us through the finite. If we go the other direction we end up with the same theology as Islam. And we make a false idol of Holy Scriptures. Bibliolatry. The temptation for error of some adherents of Sola Scriptura. Let's hear what St. Peter has to say about sacred Scripture:
So I will always remind you of these things, even though you know them and are firmly established in the truth you now have. I think it is right to refresh your memory as long as I live in the tent of this body, because I know that I will soon put it aside, as our Lord Jesus Christ has made clear to me. And I will make every effort to see that after my departure you will always be able to remember these things.
For we did not follow cleverly devised stories when we told you about the coming of our Lord Jesus Christ in power, but we were eyewitnesses of his majesty. He received honor and glory from God the Father when the voice came to him from the Majestic Glory, saying, “This is my Son, whom I love; with him I am well pleased.” We ourselves heard this voice that came from heaven when we were with him on the sacred mountain.
We also have the prophetic message as something completely reliable, and you will do well to pay attention to it, as to a light shining in a dark place, until the day dawns and the morning star rises in your hearts. Above all, you must understand that no prophecy of Scripture came about by the prophet’s own interpretation of things. For prophecy never had its origin in the human will, but prophets, though human, spoke from God as they were carried along by the Holy Spirit. (II Peter 2:12-21)
What more sure word do we have than Scripture? Peter called Paul's writings Scripture (II Peter 3:16). Being that we have been given this sure word of God, and Peter specifically said, "I will make every effort to see that after my departure you will always be able to remember these things.", what mere words of men can compare to what the Holy Spirit directs to be written? It is not "Bibliolatry" - which is a polemical trick word that implies some people WORSHIP the Bible - but a recognition that God's word IS truth and there is nothing man can devise that supersedes its authority. He gave it to us for HIS purposes, so that we may "always remember" those things He taught us.
When someone wants to assert authority OVER and above God's word, their temptation is to falsely claim sola Scriptura is Bible worship, as if God's word is an "idol". All we need do is look at how God used His word to establish absolute truth, to combat the distortion of truth (like Jesus did with Satan after Jesus' 40 day fast in the wilderness) and to ensure we know even today the difference between Divinely-inspired words and man's wisdom, to know that God's immutable and inerrant word is written both to establish truth and as reminders to stimulate us to wholesome thinking (2 Peter 3:1). That doesn't make it an idol - it is God's voice addressed to His dearly beloved children.