The entire Word of God (The Holy Bible) is 100% true. We ignore it to our peril. Paul was God's servant, just as was Moses, David, and others whom God used to pen what HE wanted the World to KNOW. All fallible human beings. But God's Word is INFALLIBLE in that HE, as infinite Creator God saw to it that what was written was and is the Truth.
Paul is hated by modernists. But, so is Jesus Christ, Lord of Lords, and King of Kings.