The fourth commandment is, Remember the sabbath-day, to keep it holy. Six days shalt thou labor, and do all thy work; but the seventh day is the sabbath of the Lord thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy man-servant, nor thy maid-servant, nor thy cattle, nor thy stranger that is within thy gates. 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.
Ex. 20:8-11.