Deuteronomy 4:10-13

10especially the day you stood before the Lord your God at Horeb (Mount Sinai), when the Lord said to me, ‘Assemble the people to Me and I will let them hear My words, so that they may learn to fear Me [with awe-filled reverence and profound respect] all the days they live on the land, and so that they may teach their children.’

11You approached and stood at the foot of the mountain, and the mountain burned with fire to the [very] heart of the heavens: darkness, cloud and thick gloom.

12Then the Lord spoke to you from the midst of the fire; you heard the sound of the words, but you saw no form—there was only a voice.

13So He declared to you His covenant which He commanded you to follow, the Ten Commandments; and He wrote them on two tablets of stone.