In the third month, on the same day [of the month] that the Israelites had left the land of Egypt, they entered the Wilderness of Sinai.
References for Exodus 19:1
After they departed from Rephidim, they entered the Wilderness of Sinai and camped in the wilderness, and Israel camped there in front of the mountain.
Moses went up [the mountain] to God, and the Lord called to him from the mountain: "This is what you must say to the house of Jacob, and explain to the Israelites:
You have seen what I did to the Egyptians and how I carried you on eagles' wings and brought you to Me.
Now if you will listen to Me and carefully keep My covenant, you will be My own possession out of all the peoples, although all the earth is Mine,
References for Exodus 19:5
and you will be My kingdom of priests and My holy nation. These are the words that you are to say to the Israelites."
References for Exodus 19:6
After Moses came back, He summoned the elders of the people, and put before them all these words that the Lord had commanded him.
Then all the people responded together, "We will do all that the Lord has spoken." So Moses brought the people's words back to the Lord.
The Lord said to Moses, "I am going to come to you in a dense cloud, so that the people will hear when I speak with you and will always believe you." Then Moses reported the people's words to the Lord.
And the Lord told Moses, "Go to the people and purify them today and tomorrow. They must wash their clothes
and be prepared by the third day, for on the third day the Lord will come down on Mount Sinai in the sight of all the people.
Put boundaries for the people all around the [mountain] and say: Be careful that you don't go up on the mountain or touch its base. Anyone who touches the mountain will be put to death.
No hand may touch him; instead he will be stoned or shot [with arrows], neither animal or man will live. When the ram's horn sounds a long blast, they may go up the mountain."
Then Moses came down from the mountain to the people and consecrated them, and they washed their clothes.
He said to the people, "Be prepared by the third day. Do not have sexual relations with women."
References for Exodus 19:15
On the third day, when morning came, there was thunder and lightning, a thick cloud on the mountain, and a loud trumpet sound, so that all the people in the camp shuddered.
Then Moses brought the people out of the camp to meet God, and they stood at the foot of the mountain.
Mount Sinai was completely enveloped in smoke because the Lord came down on it in fire. Its smoke went up like the smoke of a furnace, and the whole mountain shook violently.
As the sound of the trumpet grew louder and louder, Moses spoke and God answered him in the thunder.
The Lord came down on Mount Sinai, at the top of the mountain. Then the Lord summoned Moses to the top of the mountain, and he went up.
The Lord directed Moses, "Go down and warn the people not to break through to see the Lord; otherwise many of them will die.
Even the priests who come near the Lord must purify themselves or the Lord will break out [in anger] against them."
But Moses responded to the Lord, "The people cannot come up Mount Sinai, since You warned us: Put a boundary around the mountain and consider it holy."
And the Lord replied to him, "Go down and come back with Aaron. But the priests and the people must not break through to come up to the Lord, or He will break out [in anger] against them."
So Moses went down to the people and told them.