God's holy days were created BEFORE the old covenant was struck. They are part of the old covenant (and new) but they exist outside of any covenant.
Besides, if you believe in the concept of Christian liberty why is it "bad" for me to observe holy days created by Jesus Christ that are IN the bible...yet it's not "bad" for you to observe days that were invented by man and are NOT in the bible?
Really? My bible shows the old covenant first being struck with Abraham in Gen 12 and especially Gen. 15. Please direct me to the passages where God's "holy days" were created before that.
You missed my points - just saying that Christianity did not exist for us until Jesus arose - everything else is Old Covenant and the Old Covenant is not binding due to the new Covenant (God didn't come up with a new set of rules and then try to complicate things for us by keeping some of the old rules clauses in effect).
I have no problem with anyone celebrating any day as an observance of God's love and goodness - we should all be as David, when celebrating the return of the Ark of the Covenant, dancing for all we are worth, no matter what others may think, in praise of the Lord.
While doing so, we should not lose sight of the fact that God gave us the New Covenant for a reason and we need to be aware of the separation between them and not get them mixed up. Muddling them gets us chastised for "falling from Grace" because we diminish the sacrifice and elevate ourselves much as the Pharisees did.