What did God establish the seventh day to be for Israel?
God established the seventh day for Israel as the holy Sabbath—a day of rest and worship. He set it apart as the holy day and later incorporated it into the Ten Commandments, mandating that Israel keep that holy Sabbath on the seventh day.
Les explains that this was instituted and set up before the Ten Commandments were given, where it mandated that Israel should have that holy Sabbath on the seventh day. As God dealt with Israel, He set up the seventh day as the day of rest, the day of worship, and the holy day, and He would incorporate it into the Ten Commandments. Les also warns against confusion today: Sunday is not the Sabbath, because it is not the seventh day but the first day.