Exodus 19:21-25

21and the LORD said to him, “Go down and warn the people not to break through to see the LORD, lest many of them perish. 22Even the priests who approach the LORD must consecrate themselves, or the LORD will break out against them.”

23But Moses said to the LORD, “The people cannot come up Mount Sinai, for You solemnly warned us, ‘Put a boundary around the mountain and set it apart as holy.’”

24And the LORD replied, “Go down and bring Aaron with you. But the priests and the people must not break through to come up to the LORD, or He will break out against them.”

25So Moses went down to the people and spoke to them.