Paul was defending the Gospel. In doing so he defended himself so as to give credibility to the messenger. He even says that if he himself preaches another Gospel let him be accursed. Paul gave names as a witness to what he did and who he was.

The letter is much more than Paul defending himself.

And in 2 Tim. 4:11 Paul says, “Luke alone is with me.” To just cut 2 Timothy 1:15 out of it’s context does not prove your point that Paul was not an Apostle. If that is your point.

“I am independent of the 12, and better than them. Whereas they walked faithfully with Jesus throughout his earthly ministry and saw his miracles and heard his teachings, I received an internal revelation of Christ which is much better. Not only that, but the top 3–Peter, James, and John–are a collection of nobodies who only seem to be something, but whatever they are doesn’t make a lick of difference to me. In truth, they’re all Judaizers! Yet, even they acknowledge that God has chosen me to preach to the Gentiles, and they can’t add anything to me. I know you’ve read in that ‘book of Acts’ that in the Jerusalem Council they added letters to me to deliver to the churches, but its a lie. In reality all they tried to add to me in the Jerusalem Council was to remember the poor, as if I wasn’t already going to do that. And, look, Peter’s a big fat hypocrite! I’ll relate to you an incident that happened in a far away place which you can’t possibly verify, and which I have no reason to share with you other than that I need to make the real apostles look bad to make myself seem like an apostle. I chewed Peter down, and that makes me the top apostles now!”

It is no wonder that after this letter, not only Galatia, but all of Asia Minor (many of which Paul established, and which includes Ephesus, Laodicea, Lystra, Derbe, Colosse) rejected Paul as a false apostle, as Paul complains to Timothy right before his death, 2nd Timothy 1:15 “This you know, that all those in Asia have turned away from me.” John also represents Jesus as having him write a letter to Ephesus (which is in Asia) and say to them on Jesus’ behalf “I know your works, your labor, your patience, and that you cannot bear those who are evil. And you have tested those who say they are apostles and are not, and have found them liars;”

You mock those who find problems with Paul, but the fact is that Paul’s claim to apostleship stands on such shaky grounds that when challenged by the Galatians to prove that he is an apostle, the best he could do was attack Peter, James, and John.