By your logic, Saul should have never become the great missionary and pastor, Paul. His past was far too tainted.
You still haven't offered a solution to the "problem" you present.
Here's the solution:
The Pope should step down, apologize for seeking his own glory through seeking this station.
He should hand the reigns to someone free of the scars of the past.
He should ask the world for forgiveness for tempting evil to smile on this day.
And it that, he would, at last truly acknowledge and rid himself of his past.