Firstly, Phil 3:6
Did Saul really believe he perfectly obeyed the whole of the moral law without one slip/was blameless concerning it? Think about it. I like the way the NIV 1984 edition puts it:
As for legalistic righteousness, faultless
OK, so you have made clear your view Paul is speaking of his life as a Christian in verses7-11. You have nothing in those verses to back that up, only your opinions.
So, in your opinion, Saul the Pharisee did not know the ten commandments, for he is speaking of when the law came to him. Neither can Saul have known lust if you are correct, though Paul told Timothy he was the chief of sinners. It isn’t credible I’m afraid. So your belief is, only when Saul became Paul did he become aware of the commandment: Thou shalt not covet. And Paul the Christian then found himself a far worse sinner than Saul the Pharisee had been, for as a Christian he became full of all manner of concupiscence. Well if that is what you wish to believe you are entitled to that view, I could never agree with you. People under the old covenant knew sin. David said no one was righteous before God. The notion God made a covenant but people did not know the ten commandments, or what that entailed is fanciful in my view. And, other Pharisees were of course full of everything unclean on the inside(note everything) Jesus said so. Do you think they really did not know of lust either? Many today will preach virtual sinless perfection for christians, but does that mean they are not aware, or conscious of sin in their own lives. If that were so, how could they have been born again? I would not condemn them all