Exodus 19:18
18 Now rMount Sinai was wrapped in smoke because the Lord had descended on it in fire. The smoke of it went up like the smoke of a kiln, and sthe whole mountain trembled greatly.
Deuteronomy 4:11
11 And myou came near and stood at the foot of the mountain, while nthe mountain burned with fire to the heart of heaven, wrapped in darkness, cloud, and gloom.