9But now that you have come to know God, or rather to be known by God, how can you turn back again to the weak and worthless elementary principles of the world, whose slaves you want to be once more?
In this context, to know God refers to conversion and faith in Jesus Christ,1 specifically the knowledge of Christ that was imparted by Paul’s preaching and appropriated by faith.2
9 But now that you have come to know God, or rather to be known by God, how can you turn back again to the weak and worthless elementary principles of the world, whose slaves you want to be once more?