You know what got me looking at the Sabbath for the first time? I looked at the Creation account and I saw >>GOD<< the all powerful, all knowing, all everything, and everlasting God... needing to rest?

Not a chance... He is God, why would He need to rest? When I asked myself that I realized something, He was setting an example. He was not tired, He was showing us what He expects of those He created. There were no "Jews" for those who want to pin Sabbath on Judaism... it was only God at that point, of course there was Adam who was less than a week old... perhaps Eve.... but that was it.
Now when I saw this I began to study and the first thing that jumped out to me was Leviticus 23. There we find all the feasts, the Sabbaths... all the set-apart days. And these days are called by God, "my feasts," and "the feasts of the LORD." Not Jewish feasts, they do them... as all Israel should. But these belong to HIM. That changes the perception one has when reading what follows. And what follows FIRST? The weekly Sabbath... then the rest of the appointed days.
So, "To whom did God give the Sabbaths?" All of His people.
"Why did He give them?" As a memorial for things He has done, things He is doing, and things He will do. These are days of rest but they are also teaching tools that reveal His intention including all the work of Messiah. He said, "the scriptures testify of me" and seeing there was no NT back then... well...
Blessings.
Ken