We owe a lot to the Jews for the preservation of the worship of the God of heaven or Yahweh. Had it not been for the Jews, the worship of Yahweh would probably have been forgotten. But God made sure that this would not happen. He chose the Jews to be His representatives; His chosen people. This was not some form of favoritism on His part but He knew that to preserve the knowledge of the creator, He had to choose a people who would enter into a covenant with Him, acknowledging him as their God and them as His people.
One of the teachings of the Bible the Jews have preserved is the observance of the Sabbath. There is never a point in history when the Jews forgot the Sabbath. It is precisely because of this reason that we can learn a lot of things on how to observe the sabbath. We however, need to do this while remembering that some traditions of men have crept into their observance just as they have crept into the christian church.
The video below presents some gems for keeping the sabbath as practiced by the Jews.