The text speaks. Verse 16 Starts with the word therefore. That means we need to consider what was said before, because what is about to be said is the conclusion. One only needs to go back a few verses to establish context.
The context is forgiveness. It says, Having been forgiven all trespasses in verse 13. Then in relation to that it says that the handwriting to the ordinances that were against and contrary to us were blotted out.
Why were they blotted out?
They are not needed anymore we have been forgiven. The handwriting to the ordinances were the judgments and ceremonies from God that Moses penned for when we sinned. These were against us and contrary to us not the ordinances themselves and certainly not the Decalogue.
The Judgments are not needed anymore because now we are forgiven through Christ. These Judgments were triumphed over through His Cross, He made a show of them openly spoiling all their powers. The meat and drink offerings, holyday, new moon and Sabbaths mentioned are from the handwriting to the ordinances according to the context. Those which pointed to Christ and His Mission.
And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses; Blotting out the handwriting to the ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross; And having spoiled principalities and powers, he made a shew of them openly, triumphing over them in it. 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 2:13-16)
Note before I make any remarks that I do not advocate being disobedient to God and his enduring moral law whatsoever. I think your claim that the Ten Commandments stood alone and apart from the Book of the Covenant is a false claim. It is one unified law. The Ten Commandments summarized the Mosaic Law, but was not apart from it. There were deeper practical applications within the "Book of the Covenant", though. The Sabbath is not a moral issue, but is a ceremonial issue, just like the rest of the calendar observances.
They pointed toward Christ and elements of his ministry and work.
And, I think that your claims regarding "handwriting" do not, in fact, refer to the Book of the Covenant, but it is talking about a list of sins against the believer prior to their salvation. It is a "list of debts".
This is the way the ESV words it:
Colossians 2:13-15 3 And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses, 14 by canceling the record of debt that stood against us with its legal demands. This he set aside, nailing it to the cross. 15 He disarmed the rulers and authorities and put them to open shame, by triumphing over them in him.
(ESV Strong's)
In fact, no believer is under the condemnation of the law. Any of the law. If they are in Christ, they are accounted as righteous. They strive to obey God but they are no longer under the condemnation of the law.
Here are some decent notes in a study bible I enjoy.
By the way, if you object to my use of notes, I really don't care. Nor do I blindly follow them as some of you have claimed. My thought is, why should I re-create the wheel when I can find a good, quick source that quotes essentially the same view? And, I know you guys have been fed doctrine from your sources as I recognize the same arguments from any SDA I've talked with.
Colossians 2:14-17 2:14
the charge of our legal indebtedness. Paul uses the metaphor of a legal bond or certificate of debt (an IOU) in which humans promise to obey what they know to be God’s will (cf. Rom 1:32). It becomes our death warrant when we fail to obey (cf. Rom 3:23) because we cannot possibly repay the debt. But God blotted out the list of debts and destroyed all the incriminating evidence against us when Christ was nailed on the cross in our place. Christ took away the burden of our guilt. Believers receive the verdict of his righteousness.
2:15
disarmed. In the crucifixion God paradoxically did to the powers what they did to Christ when they dragged him through Jerusalem, stripped him naked, treated him with contempt, and nailed the charges against him on the cross. God stripped the “powers and authorities” of their power and exposed their weakness. Christ’s victory on the cross brings freedom from the tyranny of these alien forces. triumphing over them by the cross. Roman generals celebrated their victories by marching through the streets of Rome exhibiting the spoils of war and parading their captives. Paul’s metaphor of the victory parade (2 Cor 2:14; Eph 4:8) imagines the cross as the chariot in which Christ rode as a triumphant general. Paul may envision Christ’s vanquished foes trailing behind him in humiliating defeat.
2:16
eat . . . drink . . . religious festival . . . celebration . . . Sabbath day. The opponents impose food laws and the observance of sacred days as part of their criteria for judging the Colossians’ spiritual merit. No one can invalidate their standing in Christ when they do not defer to these dictated stipulations that derive from “human tradition and the elemental spiritual forces of this world” (v. 8) rather than from Christ.
2:17
a shadow. Paul contrasts appearance and reality. NT writers viewed the OT and its laws as promises belonging to the old era that culminated with the coming of Christ (cf. Heb 10:1). Paul warns the Colossians not to retreat to this shadow-world when they have been made eligible “to share in the inheritance of [God’s] holy people in the kingdom of light” (Col 1:12).
(NIV Biblical Theology Study Bible)
As I have said, there is no teaching that Gentiles were required to observe the Sabbath in the NT. If you can find it, show it to me. You will find a mention of both Jews and Gentiles meeting in the synagogue, but this is because there were some Gentiles, called "God-fearers", who were not physically circumcised, but were interested in spiritual things, and would meet with Jews in the synagogue to hear Torah read. It is funny that you guys use this as proof the Sabbath is still a requirement, since these were synagogue meetings, and that was the only place they could hear Torah read. Personal copies of Scripture were not readily available, and some would not have known how to read anyways.
If your claim that the Sabbath is binding is true, we would find instruction by Paul to Gentiles on this issue, but we find nothing. A deafening silence. And, besides that, the all-knowing God who possesses exhaustive foreknowledge would know that the Sabbath would be neglected, if your claim is true, so he would have provided warnings against it in the NT to counteract a wrong understanding. But, we find nothing.
And, we know that Gentile slaves would not have the ability to control their diet or the conditions of their labor on any day, therefore this most certainly would have been an issue that would have required clarification. Do we obey the master when he forces us to work on the Sabbath, or do we get continually beaten? What if he only feeds us unclean meat? Do we eat it or die?