Exodus 19:1-17 NASB1995
In the third month after the sons of Israel had gone out of the land of Egypt, on that very day they came into the wilderness of Sinai. When they set out from Rephidim, they came to the wilderness of Sinai and camped in the wilderness; and there Israel camped in front of the mountain. Moses went up to God, and the LORD called to him from the mountain, saying, “Thus you shall say to the house of Jacob and tell the sons of Israel: ‘You yourselves have seen what I did to the Egyptians, and how I bore you on eagles’ wings, and brought you to Myself. Now then, if you will indeed obey My voice and keep My covenant, then you shall be My own possession among all the peoples, for all the earth is Mine; and you shall be to Me a kingdom of priests and a holy nation.’ These are the words that you shall speak to the sons of Israel.”
So Moses came and called the elders of the people, and set before them all these words which the LORD had commanded him. All the people answered together and said, “All that the LORD has spoken we will do!” And Moses brought back the words of the people to the LORD. The LORD said to Moses, “Behold, I will come to you in a thick cloud, so that the people may hear when I speak with you and may also believe in you forever.” Then Moses told the words of the people to the LORD.
The LORD also said to Moses, “Go to the people and consecrate them today and tomorrow, and let them wash their garments; and let them be ready for the third day, for on the third day the LORD will come down on Mount Sinai in the sight of all the people. 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. No hand shall touch him, but he shall surely be stoned or shot through; whether beast or man, he shall not live.’ When the ram’s horn sounds a long blast, they shall come up to the mountain.” So Moses went down from the mountain to the people and consecrated the people, and they washed their garments. He said to the people, “Be ready for the third day; do not go near a woman.”
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. And Moses brought the people out of the camp to meet God, and they stood at the foot of the mountain.
NASB1995: New American Standard Bible - NASB 1995