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.
Not that Paul has already obtained this or is already perfect, but he presses on to make it his own because Christ Jesus has made him his own.
It opens the section with humble pursuit.
12Not 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. 13Brothers, 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, 14I press on toward the goal to win the prize of God’s heavenly calling in Christ Jesus. 15All of us who are mature should embrace this point of view. And if you think differently about some issue, God will reveal this to you as well. 16Nevertheless, we must live up to what we have already attained.