Ruminating about the past is like trying to drive backward to undo a car accident.
No matter how much you think about it, worry about it or regret it, you can't change your past. Yet, there you go again thinking about the past as if you can rewrite it. Focus your time and attention to live fully in the present where you really can make a difference.
Brothers, I for my part do not consider myself to have taken possession. Just one thing: forgetting what lies behind but straining forward to what lies ahead, I continue my pursuit toward the goal, the prize of God’s upward calling, in Christ Jesus.