Exodus 19:12 "You shall set bounds for the people all around, saying, 'Beware that you do not go up on the mountain or touch the border of it; whoever touches the mountain shall surely be put to death.

Exodus 19:16 So it came about on the third day, when it was morning, that there were thunder and lightning flashes and a thick cloud upon the mountain and a very loud trumpet sound, so that all the people who were in the camp trembled.

Exodus 20:18 All the people perceived the thunder and the lightning flashes and the sound of the trumpet and the mountain smoking; and when the people saw it, they trembled and stood at a distance.

Deuteronomy 4:11 "You came near 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.

Deuteronomy 5:22 "These words the LORD spoke to all your assembly at the mountain from the midst of the fire, of the cloud and of the thick gloom, with a great voice, and He added no more. He wrote them on two tablets of stone and gave them to me.

2 Corinthians 3:7 But if the ministry of death, in letters engraved on stones, came with glory, so that the sons of Israel could not look intently at the face of Moses because of the glory of his face, fading as it was, (NASB ©1995)