The Lord commanded Moses
to tell the people of Israel, "Keep the Sabbath, my day of rest, because it is a sign between you and me for all time to come, to show that I, the Lord, have made you my own people.
You must keep the day of rest, because it is sacred. Whoever does not keep it, but works on that day, is to be put to death.
You have six days in which to do your work, but the seventh day is a solemn day of rest dedicated to me. Whoever does any work on that day is to be put to death. 1
References for Exodus 31:15
31.15 Ex 20.8-11; 23.12; 34.21; 35.2; Lv 23.3; Dt 5.12-14.
The people of Israel are to keep this day as a sign of the covenant.
It is a permanent sign between the people of Israel and me, because I, the Lord, made heaven and earth in six days, and on the seventh day I stopped working and rested." 2
References for Exodus 31:17
31.17 Ex 20.11.
When God had finished speaking to Moses on Mount Sinai, he gave him the two stone tablets on which God himself had written the commandments.