Douglas....Christians are not bound to the Holy Days you allude to...which is another topic altogether. We are free in Christ...observing these does not make one more holy or less acceptable because our position now is IN Christ as Christians...and we walk by faith.
As for the Jewish Holy Days..they were ‘shadows’ of the gospel to come....they all ‘pointed to Christ’... until He came. We are “complete” in Him as Christians. Jesus was very clear that these not be forced on the new Gentile believers.
Romans 14:3 ...The one who eats everything must not treat with contempt the one who does not, and the one who does not eat everything must not judge the one who does, for God has accepted them.
Romans 14:5.... One person considers one day more sacred than another; another considers every day alike. Each of them should be fully convinced in their own mind.
Romans 14:17.... For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit,
Again caww, that's the very topic of this article. The rise of a counterfeit Christianity that says they worship the Lord, but don't do the things he says. He created his sabbaths and his holy days for his followers to observe. Saying you are "in Christ" means that you will follow what Christ does and if you allow him he will keep His holy days.
As for the Jewish Holy Days..
Let's make no mistake about who's days these are:
Lev 23:2 "Speak to the children of Israel, and say to them: 'The feasts of the LORD, which you shall proclaim to be holy convocations, these are My feasts.
they were shadows of the gospel to come....they all pointed to Christ... until He came.
Actually Paul says they ARE shadows of things to come:
Col 2:16 Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days:
Col 2:17 Which are a shadow of things to come; but the body is of Christ.
There's no doubt that the english equivalent of the greek is "ARE". In other words, Paul, long after Christ had died and had been resurrected, referred to the holy days of the Lord as shadows of things yet to come.
And they ARE. They're predictive and symbolic of past, present and future events.
I would encourage you to check out:
Holidays or Holy Days: Does it Matter Which Days We Observe
God's Holy Day Plan: The Promise of Hope For All Mankind
I'm sure these will help with your struggle to understand scripture.
We are complete in Him as Christians. Jesus was very clear that these not be forced on the new Gentile believers. Romans 14:3 ...The one who eats everything must not treat with contempt the one who does not, and the one who does not eat everything must not judge the one who does, for God has accepted them.
This is explained in the links above...but the short answer here is that Romans chapter 14 never uses the greek terms for the Lord's holy days or sabbaths. Reading Romans 14 in context shows that Paul is referring to eating practices, likely having to do with with whether or not Christians of the day should eat otherwise clean meat that had been sacrificed to pagan idols and then later purchased in the meat market.
Take care and hope you have a good read...