The Weekly Sabbath is One of the Ten Commandments

Exodus 20:8 Remember the sabbath day, to keep it holy.

Exodus 20:9 Six days shalt thou labour, and do all thy work:

Exodus 20:11 For in six days the LORD made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the LORD blessed the sabbath day, and hallowed it.