Let us see if we can shed some light on this Sabbath issue, why not start from the beginning.
Genesis
Then God viewed everything He made, and {Look!} it was very good. So came the evening and morning of day six.
Chapter 2
So God finished heaven and earth, and all the arranging of them. God completed his work of making these things on the sixth day. And on the seventh day, He stopped making them. Then God blest the seventh day and made it holy, because He had finished all the work that He started out to do.
From Genesis and the above text, we can make some observations.
1. a day was from evening to evening, rather than morning to morning
2. God blessed and make the 7th day holy in the beginning
3. no one was told to keep the sabbath day holy
No, let's go to the book of the Exodus.
Chapter 20
‘Keep the Sabbath day and make it holy. You may work and get everything done in six days, but the seventh day is the Sabbath of your God Jehovah, and you must do no work… not you, your son, your daughter, your male servant, your female servant, your ox, your burro, any of your cattle, or any strangers that are visiting among you. Because, Jehovah made the sky, the ground, the seas and everything in them, then He rested on the seventh day. So Jehovah blest the seventh day and made it holy.
Exodus 23:22 God says to Israel:
‘If you listen to what I tell you, do everything that I tell you to do, and keep My Sacred Agreement, you will be a special people to Me above all other nations; for the whole earth is Mine. Then you will become a holy nation of Royal Priests.
Exodus 24:4-8
Then Moses [sat down] and wrote everything that Jehovah said. And early the next morning, he built an Altar at the base of the mountain using twelve stones [to represent] the twelve tribes of Israel. And he sent young men from the children of Israel to offer up whole burnt offerings and to sacrifice young calves as a peace offering to God. Then Moses took half of the blood and poured it into bowls, and he poured the other half on the Altar. Thereafter, [Moses] took the scroll of the Sacred Agreement [that he wrote] and read it to the people. And they [again] said, ‘We will do and pay attention to everything that Jehovah has said.’ Then Moses took the blood [from the bowls] and sprinkled it on the people, and he said: ‘{Look!} This is the blood of the Sacred Agreement that Jehovah has made with you over the things that you’ve [agreed to].’
The above texts illustrate how Israel and God made a covenant (sacred agreement) with one another. Observance of the Sabbath was part of that agreement.
New Testament Sabbath keeping instruction
Hebrews:
Chapter 3
Therefore, holy brothers among the calling of heavenly partakers; Let’s consider this Apostle and High Priest whom we confess, Jesus.
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‘If you should hear His voice today, don’t harden your hearts as happened in the bitter day of testing in the desert. For, that’s when your fathers tested Me to prove [My power]… yet they’d been watching what I was doing for forty years! This is the reason why I became so disgusted with that generation and said, Their hearts are always wandering, and they’ve never understood My ways. So, in My anger I swore, They will never enter My rest.’ Therefore, watch out brothers, that none of your hearts ever become wicked and unbelieving, and then cause you to pull away from the Living God!
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And just who was it that He became disgusted with for forty years? Wasn’t it those who had sinned and whose carcasses fell in the desert? And who was it that He said wouldn’t enter His Rest… if not those who disobeyed? So, we can see that they couldn’t enter [His Rest] due to their lack of faith!
Chapter 4
Therefore, we should [all] fear that some of us might be left behind when it comes to the promise of entering His rest, because we’ve had the good news preached to us, just as they did. Yet, they failed to benefit from hearing those words, because the faith of those who heard and believed didn’t rub off on them! However, those of us who have believed will enter His Rest. And although He said, ‘So, in my anger I swore that they’ll never enter My Rest,’ His work [has actually been finished] since the founding of the world! Why, in one place He said this about the seventh day: ‘God rested from all His works on the seventh day.’ And here [He said], ‘They will never enter My rest.’ So, we must conclude that some will enter it! However, those to whom this good news was first given didn’t enter it because of their disobedience.
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Therefore, let’s do everything that we can to enter that rest, so no one will fail because of disobedience.
The above is a loaded text which is tough to understand without being familiar with the exodus and travels of Israel from Egypt to the land of promise. It seems the Hebrew writer in not using the sabbath to describe the 7th day, but rather the inheritance/promise that God made to those who kept His ways (abide by the covenant/sacred agreement) in ancient Israel with the followers of Jesus who were being encouraged to keep the faith. The Sabbath in this text seems to represent the reward of the faithful rather than a day of the week.
please note:
In the Old Testament there were special high sabbaths in addition to the weekly 7th day sabbath. When you see the word sabbath, think rest rather than a day of ritualistic (which are often pagan) worship service practices.