2:16,17 - "Therefore no one is to act as your judge in regard to food or drink or in respect to a festival or a new moon or a Sabbath day, things which are a mere shadow of what is to come; but the substance belongs to Christ."
Galatians 4:9-11 But now that you have come to know God, or rather to be known by God, how is it that you turn back again to the weak and worthless elemental things, to which you desire to be enslaved all over again?
(10) You observe days and months and seasons and years.
(11) I fear for you, that perhaps I have labored over you in vain.
I fear that we waste far too much time arguing over things which are a "mere shadow of what is to come" and pay far too little attention to Christ, Himself
If a person refuses to obey Him, they don't know Him.
1Jo 2:4 He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
Joh 14:15 If ye love me, keep my commandments.
De 32:12 So the LORD alone did lead him, and there was no strange god with him.
Israel was led out of bondage when there were no strange god found in it, and into bondage when there were. If a person chooses to whore around with strange gods (Idolatry), then it is an easy step to whore around with another man's wife Adultery/Fornication/Unfaithfulness which IS Idolatry.). Any god will do, any woman will do. Same principle.
Jesus said, Joh 4:22 Ye worship ye know not what: we know what we worship: for salvation is of the Jews.
I think you need to read and study these passages from a 1st century Jewish/early Christian point of view and not from a 21st century perspective.
If you are truly interested read Are God's Holy Days Relevent Today