Exodus 19:23-25

And Moses said to the LORD, “The people cannot come up to Mount Sinai, for you yourself warned us, saying, ‘Set limits around the mountain and consecrate it.’” And the LORD said to him, “Go down, and come up bringing Aaron with you. But do not let the priests and the people break through to come up to the LORD, lest he break out against them.” So Moses went down to the people and told them.