Exodus 19:7-25

So Moses went down and called the leaders of the people together and told them everything that the LORD had commanded him. Then all the people answered together, “We will do everything that the LORD has said,” and Moses reported this to the LORD. The LORD said to Moses, “I will come to you in a thick cloud, so that the people will hear me speaking with you and will believe you from now on.” Moses told the LORD what the people had answered, and the LORD said to him, “Go to the people and tell them to spend today and tomorrow purifying themselves for worship. They must wash their clothes and be ready the day after tomorrow. On that day I will come down on Mount Sinai, where all the people can see me. Mark a boundary round the mountain that the people must not cross, and tell them not to go up the mountain or even get near it. If anyone sets foot on it, he is to be put to death; he must either be stoned or shot with arrows, without anyone touching him. This applies to both men and animals; they must be put to death. But when the trumpet is blown, then the people are to go up to the mountain.” Then Moses came down the mountain and told the people to get ready for worship. So they washed their clothes, and Moses said to them, “Be ready by the day after tomorrow and don't have sexual intercourse in the meantime.” On the morning of the third day there was thunder and lightning, a thick cloud appeared on the mountain, and a very loud trumpet blast was heard. All the people in the camp trembled with fear. Moses led them out of the camp to meet God, and they stood at the foot of the mountain. The whole of Mount Sinai was covered with smoke, because the LORD had come down on it in fire. The smoke went up like the smoke of a furnace, and all the people trembled violently. The sound of the trumpet became louder and louder. Moses spoke, and God answered him with thunder. The LORD came down on the top of Mount Sinai and called Moses to the top of the mountain. Moses went up and the LORD said to him, “Go down and warn the people not to cross the boundary to come and look at me; if they do, many of them will die. Even the priests who come near me must purify themselves, or I will punish them.” Moses said to the LORD, “The people cannot come up, because you commanded us to consider the mountain sacred and to mark a boundary round it.” The LORD replied, “Go down and bring Aaron back with you. But the priests and the people must not cross the boundary to come up to me, or I will punish them.” Moses then went down to the people and told them what the LORD had said.