If anyone else thinks he has reason for confidence in the flesh, I have more: 5 circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; as to the law, a Pharisee; 6 as to zeal, a persecutor of the church; as to righteousness under the law, blameless. 7 But whatever gain I had, I counted as loss for the sake of Christ. 8 Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ 9 and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith— 10 that I may know him and the power of his resurrection, and may share his sufferings, becoming like him in his death, 11 that by any means possible I may attain the resurrection from the dead.
12 Not that I have already obtained this or am already perfect, but I press on to make it my own, because Christ Jesus has made me his own. 13 Brothers, I do not consider that I have made it my own. But one thing I do: forgetting what lies behind and straining forward to what lies ahead, 14 I press on toward the goal for the prize of the upward call of God in Christ Jesus.
A little more than 100 years ago, one of the brightest lights of the German theological world did something that surprised everyone. He had just written his PhD thesis and it had taken the academic world by storm. He was in his early 30’s and a bright career as a university professor surely awaited him. But his shocking move was to enroll in medical school and leave Germany for equatorial Africa where he set up a clinic. His name may be familiar to you, Albert Schweitzer. You can look a Wikipedia article about him here: https://en.wikipedia.org/wiki/Albert_Schweitzer
For decades he worked in deplorable conditions in a French colony among desperately poor and needy people. He still wrote and was not shy about raising funds and collecting accolades. Eventually he won the Nobel Peace Prize. But everyone was amazed by his departure from the safe and secure career which lay open to him for the dangers of a clinic along a river in Africa. He gave up so much. Yet, Schweitzer did not see it as so strange. The Jesus of whom he wrote as a theologian was the same Jesus who had healed the sick and cared for the downtrodden and the outcasts of the first century. He always said he was answering a call to be like Christ. In this reading the Apostle Paul speaks of his own transition from a white-hot opponent of Christianity into a blazing proponent of that same faith. It required that he lose many things. He too had a promising career as a rabbi in front of him. He is glad to have lost all of it. He is striving to the only thing that really matters. Everything else is so much rubbish. In doing so, Paul was also copying that Other who gave up everything, and far more, so that He might have a treasure (Matt. 13:42). For the joy set before Him, Jesus endured the cross and despised its shame, and wields all heavenly authority (Heb. 12:2).