A Christian life is lived forewords, not backwards. 

The life we have from Christ

The life we live for Christ

Philippians 3:4b-14 (EHV)

What the world considered valuable, Paul no longer valued. What Paul valued was Christ, whom God had exalted in the resurrection. Through Christ God exalts us as well, regardless of what the world thinks of us.

If anyone else thinks that he has grounds for confidence in the flesh, I have more: 5circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; in regard to the law, a Pharisee; 6in regard to zeal, persecuting the church; in regard to the righteousness that is in the law, blameless. 7But, whatever things were a profit for me, these things I have come to consider a loss because of Christ. 8But even more than that, I consider everything to be a loss because of what is worth far more: knowing Christ Jesus, my Lord. For his sake, I have lost all things and consider them rubbish, so that I may gain Christ 9and be found in him, not having a righteousness of my own, which comes from the law, but that which comes through faith in Christ, the righteousness that comes from God by faith. 10I do this so that I may know him and the power of his resurrection and the fellowship of his sufferings, being conformed to his death, 11in the hope that in some way I may arrive at the resurrection from the dead. 12Not that I have already obtained this or have already reached the goal, but I press on to take hold of that for which Christ Jesus also took hold of me. 13Brothers, I do not consider myself to have taken hold of it yet, but there is one thing I do: Forgetting the things that are behind and straining toward the things that are ahead, 14I press on toward the goal, for the prize of the upward call of God in Christ Jesus.