Galatians 4:9-11

9But now you do know God. Or really, I should say that God knows you. So you must not turn back to serve those weak spirits that rule this world. Why do you want to obey their useless rules and become their slaves again?

10You say that certain days, or months, or seasons, or years are special. That is how you want to please God.

11I am afraid about you. I worked very much to help you. I do not want my work to have no results.