Galatians 4: 9 But now having known God, or rather being known of God, how turn ye back to the weak and beggarly elements, to which ye desire to be in bondage again?
10 Ye observe days, and months, and times, and years. I am afraid for you, lest I have laboured upon you in vain.
This teaches the church had no sacred days. Not even Sabbath. Chapter 3 said the law was Israel's schoolmaster til Jesus came. And chapter four says gentle believers were mistaken to use Israel's schoolmaster when Israel graduated from that elementary schooling themselves.