Exodus 31:17-18

New Century Version

¹⁷ The Sabbath day will be a sign between me and the Israelites forever, because in six days I, the Lord, made the sky and the earth. On the seventh day I did not work; I rested.’”

¹⁸ When the Lord finished speaking to Moses on Mount Sinai, he gave him the two stone tablets with the Agreement written on them, written by the finger of God.