The apostle Paul writes in Philippians chapter 3 that "whatever gains I had, these I have come to regard as loss because of Christ. More than that, I regard everything as loss because of the surpassing value of knowing Christ Jesus my Lord." What things is Paul writing of here? They are the way he formerly defined himself, according to human standards. Paul says "For his sake I have suffered the loss of all things, and I regard them as rubbish, in order that I may gain Christ." For Paul his identity was now in Jesus, there was to him "surpassing value" in knowing Jesus. To Paul Jesus is more than a "good feeling" or a "great man from the past". Jesus is the living Lord, true king of this earth and his pursuit in life is "knowing him." Paul writes "I want to know Christ and the power of his resurrection and the sharing of his sufferings by becoming like him in his death, if somehow I may attain the resurrection from the dead."For Paul, "knowing Jesus" is a quest, one that will entail suffering and even his death, but it is worth it all because he is on a quest to know his Lord, to share in a glorified resurrected state with him.
This is the sentiment of Christians, to "know Jesus", to have "Christ formed in us" (Galatians 4:19), to have the "Spirit of Christ" (Romans 8:9) living within us. Paul tell these Christians in Philippi they are a "commonwealth of heaven" (Philippians 3:20) they are literally a colony of heaven, dispersing the knowledge of Jesus into the world, living his kingdom, making a difference. For us as well "knowing Jesus" is going to be a quest, we come to a saving knowledge of him for sure in believing and being united with him in our baptism, but from there it will be, or should be a quest to immerse ourselves in him, to be his disciple and find our identity in him, to develop his mind (Philippians 2:5) and live these things in practice, in every way in life.