The mark (Greek word skopos) is used in archery to be the target or what we are aiming for. This is (in the context) to know Christ and the prower of his resurrection, not just to know who he is, but to become like Him. Our aim is live in love and with the fruit of the spirit. To that we are pursuing a lifetime goal. We also are doing this together as one body. Let's not look back, but focus on the "growing up into Christ."