No one denies he lived. No one denies his authorship of much of the New Testament. No one claims he was uneducated or unstable - his writings won't permit it. No one makes a serious case that he was an impostor or a fraud - his beliefs cost him too much for that. And despite any ongoing attempts to reinterpret some of Paul's arguments, the accuracy of his writings as we have them, stand the test.
This man was a credible witness. As credible as any who has ever taken the stand in any court room throughout history. I was thinking of this today as I read Paul's letter to the Galatians. I was suddenly astounded by the power of his simple explanations of his belief:
... I want you to know, brothers, that the gospel I preached is not something that man made up. I did not receive it from any man, nor was I taught it; rather, I received it by revelation from Jesus Christ.
For you have heard of my previous way of life in Judaism, how intensely I persecuted the church of God and tried to destroy it. I was advancing in Judaism beyond many Jews of my own age and was extremely zealous for the traditions of my fathers. But when God, ...was pleased to reveal his Son in me so that I might preach him among the Gentiles, I did not consult any man, nor did I go up to Jerusalem to see those who were apostles before I was, but I went immediately into Arabia and later returned to Damascus. ...
I assure you before God that what I am writing you is no lie.... Galatians 1 (11 - 20)
(this video portion is from the book of Acts, but Paul's story is the same)
And such was Paul's unwavering message until the end of his days.