First of all, God demonstrates patterns in scripture, over and over. One of those patterns is the number seven, which represents completeness. I have written about the number seven many times.
The first two chapters of Genesis describe how the LORD worked for six days, and then He set the seventh day apart. The scriptures are filled with this idea of separation, setting apart the holy from the profane (or common).
This seventh day of rest points to the covenant that the LORD would make with the Israelites at Sinai, which included the command to keep the Sabbath holy - set apart from the rest of the week. And throughout history, it has been said that it wasn't so much that the Jews kept the Sabbath, but that the Sabbath kept the Jews! It is one of the major things that has set them apart as a people.
And in turn, that seventh day of rest points clearly to Yeshua, our Messiah, who is called our rest. Psalm 95 speaks of avoiding His wrath and entering His rest. The writer of Hebrews quotes this psalm in chapters 3 and 4 when speaking of entering His rest.
So what does it mean to enter His rest?
For one thing, it means that He did all the work of redemption for us. We can rest in His provision.
But there is an interesting pattern in scripture, as well. The six days of creation are a snapshot of the six thousand years of human history, with the promise of a seventh millennium of rest to come in the Messianic kingdom. I wrote a post about this pattern once a few years ago, so here is a link to that study if you want to read about it.
Also, we can do biblical math and clearly see that we can count about 2000 years from Adam to Abraham, about 2000 years from Abraham to Yeshua, and about 2000 years from Yeshua to now. Knowing that the scripture promises us a one-thousand year reign of peace with Messiah as king, we can apply this pattern and know that His return is very soon!
Continuing with the idea of separation, we see that the very first spoken word of the LORD uses this principle: Let there be light.
Right away on day 1, God separated the darkness from the light. This is so profound. The sun, moon, and stars were not created until day four. So just like in Revelation 22:5, the LORD Himself is the light:
There shall be no night there: They need no lamp nor light of the sun, for the Lord God gives them light.
In the first two verses of scripture, we see this progression: