Genesis 2:1-3 "Thus the heavens and the earth were completed, and all their hosts. And by the seventh day God completed His work which He had done; and He rested on the seventh day from all His work which He had done. Then God blessed the seventh day and sanctified it, because in it He rested from all His work which God had created and made."
Genesis 2 is the only place the subject of the Sabbath is mentioned before the institution of the Mosaic Law. Technically speaking, it is not really even mentioned there, because the word Sabbath does not appear in the text. However, the concept of resting on the seventh day is found there. What does this passage actually teach about the Sabbath day? It teaches very clearly that God made all things in six days, and that He rested on the seventh day. Why did God rest? Was He exhausted from all His efforts to make the universe? Of course not. God rested in the enjoyment of what He had created. He rested because His work was finished. He stopped working because He was done working. It's that simple. We dare not read any kind of fatigue or weariness of God into this text. God simply rested because He totally accomplished what He set out to do.
Those Christians who hold to the Seventh Day View and the Christian Sabbath View believe that Genesis 2 reveals the Sabbath to be a creation ordinance. That is to say, they believe God bound Adam and Eve to keep the Sabbath in Genesis 2, and thus the Sabbath is perpetually binding on all mankind in the same way that all of God's moral laws are binding on all men. However, an honest examination of the text reveals that nothing is stated about God commanding man to keep the Sabbath. In other passages of the early chapters of Genesis we do find God giving clear commands.
For example in Genesis 1:28 God says, "Be fruitful and multiply, and fill the earth, and subdue it; and rule over the fish of the sea and over the birds of the sky, and over every living thing that moves on the earth." Additionally in Genesis 2:16-17 Scripture records, "And the Lord God commanded the man, saying, 'From any tree of the garden you may eat freely; but from the tree of the knowledge of good and evil you shall not eat, for in the day that you eat from it you shall surely die.'" However, Genesis 2:1-3 records no command of God. Rather, it gives us historical narrative. It details the fact that God rested on the seventh day. Why then, do so many Christians believe that Genesis 2 is a creation ordinance requiring perpetual obedience to the Sabbath? The answer is found in Genesis 2:3. There it says that God blessed the seventh day and sanctified it. Proponents of the Sabbath as a creation ordinance pack all sorts of things into the words "blessed" and "sanctified." They believe that by these words, we must understand that God set apart the seventh day from creation as a day in which all men must cease from work to emulate their Creator. However, the startling truth is that we have absolutely no evidence that anyone ever kept the Sabbath until Israel did so in Exodus 16 - about 2,400 years later! All we know for certain is that God reserved a day for Himself from the time of the creation. Much later at Sinai He would give His day to the Jews as part of the Mosaic Law.