The sabbath, as was circumcision and other commands, were first given as part of the body of the law from the Old Covenant. On "EVERY Sabbath" there was to be a burnt offering.
If you choose to observe or/and go back under an OT law:
Ye shall not add unto the word which I command you, neither shall ye diminish oughtfrom it, that ye may keep the commandments of the LORD your God which I command you. Deuteronomy 4:2
( the same "add not" and "diminish ought" applies to the NEW Covenant which the church has polluted by adding in dozens of unscriptural traditions and doctrines. *see Revelation 22:18-19)
God said in the law "DO ALL" many, many times, and this was repeated by Paul and James, and as Paul wrote in Gal. 4:21 "Tell me, ye that desire to be under the law, do ye not hear the law?"
Lev 19:37 And ye shall observe all my statutes, and all mine ordinances, and do them
Deut 31:12 ... and fear the LORD your God, and observe to do all the words of this law
Gal 5:3 Yea, I testify again to every man that receiveth circumcision, that he is a debtor to do the whole law. 4) Ye are severed from Christ, ye (who) would be *justified by the law; ye are fallen away from grace. *to renderjust or innocent:
James 2:10 For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all. Where was circumcision commanded?
-In the law, of course. -Just like the sabbath, the feasts, and a multitude of other commands that confused Christians are entangled with. (Gen 17:13/ Lev 12:3)
"This law"included every sabbath law and command:
Exodus 31:14 Ye shall keep the sabbath therefore; for it is holy unto you: every one that defileth it shall surely be put to death: for whosoever doeth any work therein, that soul shall be cut off from among his people.
He said over and over and over : "Do ALL" to them who were under the law. (at least 75x God said "all") The sabbath was part of the law, whether you choose it as the 4th commandment, or obey the "do all.." requirements of the sabbath law obsevances.
On "EVERY Sabbath" a burnt offering:
"On the Sabbath day, make an offering of two lambs a year old without defect, together with its drink offering and a grain offering of two-tenths of an ephah of fine flour mixed with oil. This is the burnt offering for every Sabbath, in addition to the regular burnt offering and its drink offering" (Num. 28:9,10).
This OT command for Sabbath keepers is clearly forbidden under the New Covenant in light of the book of Hebrews. The early Christians didn't do this and, therefore, did not keep the Saturday Sabbath command like Israel (Ex. 20:8-11 cf. Num. 28:9,10).
On "every sabbath yet another"everlasting covenant"Levitical Sabbath command was to:
5 ...take fine flour, and bake twelve cakes thereof: two tenth parts of an ephah shall be in one cake.
6 And thou shalt set them in two rows, six on a row, upon the pure table before the Lord.
7 And thou shalt put pure frankincense upon each row, that it may be to the bread for a memorial, even an offering made by fire unto the Lord.
8 Every sabbath day he shall set it in order before the LORD continually; it is on the behalf of the children of Israel, an everlasting covenant.
9 And it shall be for Aaron and his sons; and they shall eat it in a holy place: for it is most holy unto him of the offerings of the Lord made by fire by a perpetual statute. -Lev.24.
YO!, -sabbath dudes, law-up on that.
We all know it is impossible to sacrifice a lamb on every sabbath, there is no Levitical priesthood for the church, no physical altar, there is no "holy place" in the land of Israel, and no twelve cakes sprinkled with frankincense for the sons of Aaron to eat in perpetuity.
What a offense that would be, to Jesus' (Yeshua's) sacrifice. Those who insist they are keeping the sabbath, and insist that others keep it the way they do have a huge problem.
By these verses we can see that according to the letter, they have already broken it, and thereby put themselves under the laws curse. (sickness, death, debt, plagues, problems, anxiety, and more. -Deut. 28)
In Acts 15 the Jewish apostles, elders, and the whole church discussed what, if any mattters from the law should be observed by the growing churches scattered across the region.
Here is what the Jewish apostles and Jewish elders wrote the churches:
28 For it seemed good to the Holy Spirit, and to us, to lay upon you no greater burden than these necessary things:
29 that ye abstain from things sacrificed to idols, and from blood, and from things strangled, and from fornication; from which if ye keep yourselves, it shall be well with you. Fare ye well.
30 So they, when they were dismissed, came down to Antioch; and having gathered the multitude together, they delivered the epistle. 31 And when they had read it, they rejoiced for the consolation.
-Acts 15
To "keep" the sabbath today is to simply rest from your own efforts to save, heal, preserve, or deliver yourself by your own efforts. The true "rest" is to rest by trusting in the sure promises of God found in the New Covenant.
And what was the "burnt offering" a shadow of? He tells us in
Hebrews 10:12 But he, when he had offered one sacrifice for sins for ever, sat down on the right hand of God
Romans 12:1 I beseech you therefore, brethren, by the mercies of God, to present your bodies a living sacrifice, holy, acceptable to God, which is your spiritual service.
It is when we deny our self-life to serve God and forgoe our own pleasures and desires.