Paul said this:
"But whatever was to my profit I now consider loss for the sake of Christ. What is more, I consider everything a loss compared to the surpassing greatness of knowing Christ Jesus my Lord, for whose sake I have lost all things. I consider them rubbish, that I may gain Christ and be found in him, not having a righteousness of my own that comes from the law, but that which is through faith in Christ—the righteousness that comes from God and is by faith. I want to know Christ and the power of his resurrection and the fellowship of sharing in his sufferings, becoming like him in his death, and so, somehow, to attain to the resurrection from the dead.
Not that I have already obtained all this, or have already been made perfect, but I press on to take hold of that for which Christ Jesus took hold of me. Brothers, I do not consider myself yet to have taken hold of it. But one thing I do: Forgetting what is behind and straining toward what is ahead, I press on toward the goal to win the prize for which God has called me heavenward in Christ Jesus.
All of us who are mature should take such a view of things. And if on some point you think differently, that too God will make clear to you. Only let us live up to what we have already attained. "
God says this through Isaiah:
"Forget the former things;
do not dwell on the past.
See, I am doing a new thing!
Now it springs up; do you not perceive it?
I am making a way in the desert
and streams in the wasteland. "