The Sabbath
On Creation
After the creation of the earth, God set himself an ezample to rest on the Seventh Day, calling it the Sabbath. Hence God gave Israel the law for the Sabbath to provide rest, reflection, and a way to honor Him as Creator.
And on the seventh day God ended His work which He had made; and He rested on the seventh day from all His work which He had made.
3 And God blessed the seventh day and sanctified it, because in it He had rested from all His work which God created and made. Genesis 2:2–3
Reaffirmed At Mount Sinai
During the Exodus God reaffirmed the keeping of the seventh day to keep it holy. Again the Sabbath was established as a day of rest to remember God’s creation and his work, with the command to refrain from work as a way to honor him.
8 “Remember the Sabbath day, to keep it holy. 9 Six days shalt thou labor and do all thy work;
10 but the seventh day is the Sabbath of the Lord thy God. In it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates.
11 For in six days the Lord made heaven and earth, the sea, and all that in them is, and rested the seventh day. Therefore the Lord blessed the Sabbath day and hallowed it. Exodus 20:8-11

First Among Other Feasts
The Weekly Sabbath is stipulated in Leviticus 23 among Other Fesivals
The weekly Sabbath: six days shall work be done; recurring every week, and being the most important as well as the oldest of all festivals, the Sabbath introduces the other holydays.
1 And the Lord spoke unto Moses, saying, — this isn’t a law of Moses, but a Command of God convey to all the Israelites through Moses; thus it is a Command of God as “it shall be a statute for ever throughout your generations (v14).”
2 “Speak unto the children of Israel and say unto them: ‘Concerning the feasts of the Lord, which ye shall proclaim to be holy convocations, even these are My feasts.
— as the festivals discussed here were to be solemnly kept by the children of Israel, Moses is ordered to address these regulations to them;
— concerning the feasts of the Lord; better, these are festivals of the Lord which ye shall proclaim as holy convocations, these are my festivals; that is, the following festivals God claims as His, on which solemn assemblies are to be held in the sanctuary and in the land of Israel.
3 “‘Six days shall work be done, but the seventh day is the Sabbath of rest, a holy convocation. Ye shall do no work therein; it is the Sabbath of the Lord in all your dwellings.
The Sabbath is a Sign
The Sabbath is a Sign, a Seal of Bondage.
“You are to speak to the people of Israel and say, ‘Above all you shall keep my Sabbaths, for this is a sign between me and you throughout your generations, that you may know that I, the Lord, sanctify you” Exodus 31:13
Although Christians may justify themselves that they could worship God on Sunday or anyday, not just on Saturday, the sign “that I, the Lord, sanctify you” is specifically given for those who kept it on the Sabbath, on the Seventh Day!
That is, Christians may keep Sunday or any day as their Sabbath, but there is no promise that God would sanctify them as a sign between God and those he regarded as his people.
Let this sinks in: God, by declaring he would sanctify anyone who observes his Sabbath, is bound by his own word to uphold it. However, when Christians choose to keep it on Sunday or any other day, God is not bound by that promise. They are left to their own devices, much like Adam and Eve after being driven out of the Garden of Eden. They would be entirely on their own.

