Brian, I have only provided scripture for this OP. They are Gods Words not my words and there is no error in them. Gods Words are the very definition of what truth is (John 17:17) according to the scriptures.
We both know that not all people who use God's Words use them correctly. But you do not just use God's Words, you comment on them and make assumptions about them etc and that is fine because interpretation is what we do. And yes God's word is truth but we can't just pick and choose what we believe in God's Word or we make the Bible contradict itself. This is something we all need to be looking at in our interpretations. I hope I am not doing it, and sometimes I think I might be.
According to the scriptures, sin is the transgression of Gods law and not believing and following what Gods Word says. That is what the scriptures say not me (1 John 3:4; Romans 14:23; Romans 3:20 and Romans 7:7) and according to James in James 2:10-11 if we break anyone of them we stand guilty before God of sin and breaking all of them.
1 John 3:3 And everyone who has this hope in Him purifies himself, just as Christ is pure. 4 Everyone who practices sin practices lawlessness as well. Indeed, sin is lawlessness.
5 But you know that Christ appeared to take away sins, and in Him there is no sin.…
Yes Christians seek to do away with sin in their lives and if it was clear that keeping Saturday as the Sabbath was a command for Christians we would seek to do that so that we did not sin. Sin is breaking the law, but not all laws as written in the OT are to be kept literally and to the letter and that is the question we are trying to answer.
Romans 3:9 What then? Are we Jews any better off? No, not at all. For we have already charged that all, both Jews and Greeks, are under sin, 10 as it is written:
“None is righteous, no, not one;
11 no one understands;
no one seeks for God.
12 All have turned aside; together they have become worthless;
no one does good,
not even one.”
13 “Their throat is an open grave;
they use their tongues to deceive.”
“The venom of asps is under their lips.”
14 “Their mouth is full of curses and bitterness.”
15 “Their feet are swift to shed blood;
16 in their paths are ruin and misery,
17 and the way of peace they have not known.”
18 “There is no fear of God before their eyes.”
19 Now we know that whatever the law says it speaks to those who are under the law, so that every mouth may be stopped, and the whole world may be held accountable to God. 20 For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin.
Gentiles sin without the law just as they can fulfill the requirements of the law without the law which means they don't have to keep the Sabbath to do that and that also means that a Christian who does not think that the Saturday Sabbath is something God commands Christians to keep, can also fulfill the requirements of the law without Saturday Sabbath. Jews are under the law and Christians are not under the law. We get our knowledge of sin through the law, the whole of God's Word, in our hearts, both as we come to know God's Word and as the Spirit has spread abroad His Love in our heart and for us whatever we do that is not done in faith is sin, and of course it breaks God's law at some point, and at least in breaking the most important commandments.
Romans 5:5 And hope does not disappoint us, because God has poured out His love into our hearts through the Holy Spirit, whom He has given us.
Romans 14:22 The faith that you have, keep between yourself and God. Blessed is the one who has no reason to pass judgment on himself for what he approves. 23 But whoever has doubts is condemned if he eats, because the eating is not from faith. For whatever does not proceed from faith is sin.
So I am happy with how I keep the Sabbath even if it is not the 7th day Sabbath, and even if it was, I would be happy with how I keep it, especially if I have not sinned on that day, and kept it holy. And Jesus did not let people judge Him in how He kept the Sabbath and I do not let people judge me in that also. But it between God and myself and your conscience about it is different to mine.
Romans 7:1 Or do you not know, brothers—for I am speaking to those who know the law—that the law is binding on a person only as long as he lives? 2 For a married woman is bound by law to her husband while he lives, but if her husband dies she is released from the law of marriage. 3 Accordingly, she will be called an adulteress if she lives with another man while her husband is alive. But if her husband dies, she is free from that law, and if she marries another man she is not an adulteress.
4 Likewise, my brothers, you also have died to the law through the body of Christ, so that you may belong to another, to him who has been raised from the dead, in order that we may bear fruit for God. 5 For while we were living in the flesh, our sinful passions, aroused by the law, were at work k
in our members to bear fruit for death. 6 But now we are released from the law, having died to that which held us captive, so that we serve in the new way of the Spirit and not in the old way of the written code.
7 What then shall we say? That the law is sin? By no means! Yet if it had not been for the law, I would not have known sin. For I would not have known what it is to covet if the law had not said, “You shall not covet.” 8 But sin, seizing an opportunity through the commandment, produced in me all kinds of covetousness. For apart from the law, sin lies dead.
Yes we know what sin is because of the law and we break the law when we sin but that does not mean that we sin when we break the letter of the law, especially a law that God has not commanded Christians to keep. It is good to be careful we do not read things back to front.
James 2:8 If you really fulfill the royal law according to the Scripture, “You shall love your neighbor as yourself,” you are doing well. 9 But if you show partiality, you are committing sin and are convicted by the law as transgressors. 10 For whoever keeps the whole law but fails in one point has become guilty of all of it. 11 For he who said, “Do not commit adultery,” also said, “Do not murder.” If you do not commit adultery but do murder, you have become a transgressor of the law. 12 So speak and so act as those who are to be judged under the law of liberty. 13 For judgment is without mercy to one who has shown no mercy. Mercy triumphs over judgment.
So loving your neighbour as yourself fulfills the requirement of the law and not doing that shows that we have broken the law and are a law breakers.
From this site: What is the law of liberty? | GotQuestions.org
We find the law of liberty first mentioned in James 1:25, “But the one who looks into the perfect law, the law of liberty, and perseveres, being no hearer who forgets but a doer who acts, he will be blessed in his doing.” James here refers to the gospel, which, although it is called here a law, is not, strictly speaking, a law comprised of requirements and enforced by sanctions. Rather, it is a declaration of righteousness and salvation by Christ, an offer of peace and pardon by Him, and a free promise of eternal life through Him. The juxtaposition of the two contradictory terms—“law” and “liberty”—made the point, especially to the Jews, that this was an entirely new way of thinking about both. Paul uses this same technique when he refers to the “law of faith” in Romans 3:27.
The perfect liberty found in Christ fulfills the “perfect law” of the Old Testament because Christ was the only one who could. Those who come to Him in faith now have freedom from sin’s bondage and are able to obey God. Christ alone can set us free and give us true liberty (John 8:36).
The phrase “law of liberty” is found again in James 2:12. In this portion of his epistle, James is discussing the sin of showing partiality within the church. He reminds his hearers that to show favoritism toward others is a violation of the command to love our neighbor as we love ourselves. Jesus Himself reminded us that all of the Law that God gave to Moses could be summed up into one concise principle—to love God with all the heart, soul and mind, and to love our neighbor as ourselves (Matthew 22:37–40).
And having obtained mercy ourselves we also give mercy to others so God can show mercy to us and live by the royal law of loving our neighbour as ourselves.
So anyway James 2:10-11 is not really just saying that if we break one commandment we are guilty of breaking all of them,,,,,,,,,,,,,,,,, and it certainly is not saying anything about the Saturday Sabbath being a command for Christians to keep.