Deuteronomy 4:10-13

4:10 You stood before the Lord your God at Horeb and he said to me, “Assemble the people before me so that I can tell them my commands. Then they will learn to revere me all the days they live in the land, and they will instruct their children.” 4:11 You approached and stood at the foot of the mountain, a mountain ablaze to the sky above it and yet dark with a thick cloud. 4:12 Then the Lord spoke to you from the middle of the fire; you heard speech but you could not see anything – only a voice was heard. 4:13 And he revealed to you the covenant he has commanded you to keep, the ten commandments, writing them on two stone tablets.

Deuteronomy 4:33

4:33 Have a people ever heard the voice of God speaking from the middle of fire, as you yourselves have, and lived to tell about it?