Exodus 19:9, 20, 24

And the LORD said to Moses, “Behold, I come to you in the thick cloud, that the people may hear when I speak with you, and believe you forever.” So Moses told the words of the people to the LORD.

Then the LORD came down upon Mount Sinai, on the top of the mountain. And the LORD called Moses to the top of the mountain, and Moses went up.

Then the LORD said to him, “Away! Get down and then come up, you and 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.”