Galatians 4:9-11

4:9 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 basic forces? Do you want to be enslaved to them all over again? 4:10 You are observing religious days and months and seasons and years. 4:11 I fear for you that my work for you may have been in vain.