But you said before:
The picture we are given in our New Testament sources of Saul, in the days before his conversion to Jesus, is contradictory and suspect.
Where did the "contradictory" and "suspect" picture of Paul as a self-admitted Pharisee come from then?
Paul admitted that he arrested and persecuted Christians. This was work of the Sadducces, not the Pharisees. How do you explain that contradiction?