The best thing to do with the past is to learn from it, while keeping our eyes on today and looking forward to the days to come!
Jesus talks about a man who "looks back" because he is not ready for service in the kingdom of God (Luke 9:62). Now what that passage is telling us is that the past can be a distraction that keeps us from being what the Lord needs us to be today! The apostle Paul talks about "forgetting what is behind" and moving on toward the things that God has ahead (Philippians 3:13). We've got to stay centered in today, seeking to honor God and living for his future. Remember what Jesus taught us to pray: "... your will be done, on earth as it is in heaven" (Matthew 6:10 TNIV).