Exodus

Moreover also I gave them my sabbaths, to be a sign between me and them, that they might know that I am the Lord that sanctify them.

And hallow my sabbaths; and they shall be a sign between me and you, that ye may know that I am the Lord your God.

Remember the sabbath day, to keep it holy.

If thou turn away thy foot from the sabbath, from doing thy pleasure on my holy day; and call the sabbath a delight, the holy of the Lord, honourable; and shalt honour him, not doing thine own ways, nor finding thine own pleasure, nor speaking thine own words:

And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made.