Exodus 19:10-15

10Adonai said to Moses, “Go to the people, and sanctify them today and tomorrow. Let them wash their clothing.

11Be ready for the third day. For on the third day Adonai will come down upon Mount Sinai in the sight of all the people.

12You are to set boundaries for the people all around, saying, ‘Be very careful not to go up onto the mountain, or touch the border of it. Whoever touches the mountain will surely be put to death.

13Not a hand is to touch it, but he will surely be stoned or shot through. Whether it is an animal or a man, it will not live.’ When the shofar sounds, they may come up to the mountain.”

14Then Moses went down from the mountain to the people, consecrated them, and then, they washed their clothing.

15He said to the people, “Be ready for the third day. Do not draw near your wives.”