Remember I Corinthians 2:10 - these things are revealed through God's Spirit. Now, verse 13 is very revealing.
Brethren, does that sound like somebody who loved the truth of God? If this man loved the truth of God before conversion, then why did he persecute the true church - who had the true religion, who had the true Word of God, who had the true Messiah?
Did you notice that? For the tradition of the fathers - not for the truth of God! That is what Paul was zealous for. The traditions of the fathers - which is equated with Judaism right in the context.
Now, was Judaism the religion of Moses? Was Judaism the truth of the Old Testament? Brethren, by this apostle's own admission (in Romans 7, you can check it out yourself), Paul did not even understand what sin is. Romans 7:7 - he said he did not know, until the law came (until the Word came). Then he said: Sin revived and I died. (Romans 7:9)
For the first time in his life, upon conversion, he had a clear and a true understanding of what sin is. And when he said, I died; it means that he repented. And he was baptized in the water, buried.
Even the great Paul had only a cursory knowledge of the truth of God. What he was zealous in, brethren, was the religion of the Jews! That is, the traditions of his fathers. This is the same man who said that he was a sinner above all sinners because he persecuted the church.
Do you honestly think that someone attuned to the truth of God would be persecuting the church? Or, let me make that even more personal. Do you think that somebody attuned to the truth of God would be persecuting the Messiah? Do you realize there in Acts 9, where he was converted, that Christ said to him (when He appeared to him), Saul, Saul, why are you persecuting Me?
Was the apostle Paul an ignorant man? He was not; the man was a genius, biblically. He understood scriptures. He understood the traditions of his Father. But you know even the apostle Paul could not understand until God revealed it to him. We have to understand this because the apostle Paul was persecuting the church.
Here the apostle Paul did not understand, as brilliant as he was.