That may be the reason why most Christians do not keep the old covenant Sabbath. But there are us Christians who know we don't have to because we have been brought near to God through the new and better and perfect and never ending way of Christ's body. We don't need to do something in the old covenant to accomplish what God has already permanently done for us through the New Covenant way of faith in Christ.
We've already been brought into Sabbath Rest through Christ, so there's no reason to seek to be in a Sabbath Rest that we are already in by keeping the old covenant Sabbath requirement.
1. Showing appreciation is showing sincerity and love which encompasses one of the First and Greatest Commandments.
2. Dismissing the Sabbath as an old covenant antiquated ritual seems disingenuous to the laws and the prophets of who Christ was one also.
The following verses come to mind but speaking in general terms and not towards you directly.
Dan 7:25 And he shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be given into his hand until a time and times and the dividing of time.
Rev 14:12 Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.
2Co 4:3 But if our gospel be hid, it is hid to them that are lost:
2Co 4:4 In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.
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3. Sun day worship seems to be many modern day Christians keeping the sabbath on their own terms instead of the appointed times: This Seem to be a lack of respect, fear, love, etc.
To my knowledge doing good works of The Father or resting from servantile work, burdens, and stresses seem to be appropriated on the seventh day of the week as a memorial to Creation and Appreciation of The Works of The Father.
1Ti 1:8 But we know that the law is good, if a man use it lawfully;
Ecc 12:13 Let us hear the conclusion of the whole matter: Fear God, and keep his commandments: for this is the whole duty of man.
1Jn 5:2 By this we know that we love the children of God, when we love God, and keep his commandments.
1Jn 5:3 For this is the love of God, that we keep his commandments: and his commandments are not grievous.
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Christ fulfilled the law of not committing adultery but that should not mean that the law of not committing adultery is destroyed; Christ fulfilled the law of keeping the sabbath but that should not mean that the law of not keeping the sabbath is destroyed.
Mat 5:17 Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
Paul kept the sabbath and was also a follower of Christ who kept the sabbath.
1Co 11:1 Be ye followers of me, even as I also am of Christ.
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Apologies I can get long winded.