Exodus 19:18
King James Version
“And mount Sinai was altogether on a smoke, because the LORD descended upon it in fire: and the smoke thereof ascended as the smoke of a furnace, and the whole mount quaked greatly.”
Context
15And he said unto the people, Be ready against the third day: come not at wives.
16And it came to pass on the third day in the morning, that there were thunders and lightnings, and a thick cloud upon the mount, and the voice of the trumpet exceeding loud; so that all the people that in the camp trembled.
17And Moses brought forth the people out of the camp to meet with God; and they stood at the nether part of the mount.
18And mount Sinai was altogether on a smoke, because the LORD descended upon it in fire: and the smoke thereof ascended as the smoke of a furnace, and the whole mount quaked greatly.
19And when the voice of the trumpet sounded long, and waxed louder and louder, Moses spake, and God answered him by a voice.
20And the LORD came down upon mount Sinai, on the top of the mount: and the LORD called Moses to the top of the mount; and Moses went up.
21And the LORD said unto Moses, Go down, charge the people, lest they break through unto the LORD to gaze, and many of them perish.