Exodus 19:16-24

16On the third day, when morning came, there was thunder and lightning, a thick cloud on the mountain, and a very loud blast from a ram’s horn, so that all the people in the camp shuddered.

17Then Moses brought the people out of the camp to meet God, and they stood at the foot of the mountain.

18Mount Sinai was completely enveloped in smoke because the Lord came down on it in fire. Its smoke went up like the smoke of a furnace, and the whole mountain shook violently.

19As the sound of the ram’s horn grew louder and louder, Moses spoke and God answered him in the thunder.

20The Lord came down on Mount Sinai at the top of the mountain. Then the Lord summoned Moses to the top of the mountain, and he went up.

21The Lord directed Moses, “Go down and warn the people not to break through to see the Lord; otherwise many of them will die.

22Even the priests who come near the Lord must consecrate themselves, or the Lord will break out in anger against them.”

23Moses responded to the Lord, “The people cannot come up Mount Sinai, since you warned us: Put a boundary around the mountain and consecrate it.”

24And the Lord replied to him, “Go down and come back with Aaron. But the priests and the people must not break through to come up to the Lord, or he will break out in anger against them.”