Galatians 4:8-9

But, formerly, when you did not have da'as (knowledge) of HASHEM, you were avadim serving that which is by nature not HaEl Ha'Amiti (the true G-d). But, now, having known HASHEM, or rather having been known by HASHEM, how is it that you are returning to the weak and beggarly yesodot (rudiments) of the Olam Hazeh to which again you want to renew your service as avadim?