Exodus 19:10-13

Then the LORD said to Moses, “Go to the people and consecrate them today and tomorrow, and let them wash their clothes. And let them be ready for the third day. For on the third day the LORD will come down upon Mount Sinai in the sight of all the people. You shall set bounds for the people all around, saying, ‘Take heed to yourselves that you do not go up to the mountain or touch its base. Whoever touches the mountain shall surely be put to death. Not a hand shall touch him, but he shall surely be stoned or shot with an arrow; whether man or beast, he shall not live.’ When the trumpet sounds long, they shall come near the mountain.”