The Israelites arrive at the mountain of God. Yahweh asks whether they will agree to be his people, and the people accept. The people gather at the foot of the mountain, and with thunder and lightning, fire and clouds of smoke, and the sound of trumpets, and the trembling of the mountain, God appears on the peak, and the people see the cloud and normally means voice, but a few verses earlier (Exodus 19:16) it has been used to mean "thunder", in the context of the thunder and lightning from the mountain. It is therefore not clear exactly what "beqol" means here. The implication of Exodus 20:18-19 is that the people hear only thunder and trumpets and for this reason appoint Moses as their mediator with God: "And the people saw the thunder and the lightning and the sound of the trumpet and the mountain smoking...And they said [to Moses], "You speak with us, so we may listen, but let God not speak with us or we will die." Some translations therefore have "thunder" instead of "voice". Moses and Aaron are told to ascend the mountain. God pronounces the Ten Commandments (the Ethical Decalogue) in the hearing of all Israel.
Moses goes up the mountain into the presence of God, who pronounces the Covenant Code, (a detailed code of ritual and civil law), and promises Canaan to the Israelites if they obey. Moses descends and writes down Yahweh's words and the people agree to keep them. Yahweh calls Moses up the mountain together with Aaron and the elders of Israel, and they feast in the presence of Yahweh. Yahweh calls Moses up the mountain to receive a set of stone tablets containing the law, and he and Joshua go up, leaving Aaron in charge. Yahweh appears on the mountain "like a consuming fire" and calls Moses to go up, and Moses goes up the mountain.
Yahweh gives Moses instructions for the construction of the tabernacle so that God can dwell permanently amongst the Israelites, as well as the priestly vestments, the altar and its appurtenances, the ritual to be used to ordain the priests, and the daily sacrifices to be offered. Aaron is appointed as the first High Priest, and the priesthood is to be hereditary in his line.
Then Yahweh gives to Moses the two stone tablets containing these instructions, written by God's own finger.
Aaron makes a golden calf, which the people worship. God informs Moses and threatens to kill them all, but relents when Moses intercedes for them. Moses comes down from the mountain, smashes the tablets in anger, and commands the Levites to massacre the disobedient. Yahweh commands Moses to make two new tablets on which He will personally write the words that were on the first tablets. Moses ascends the mountain, God dictates the Ten Commandments (the Ritual Decalogue), and Moses writes them on the tablets.
Moses descends from the mountain, and his face is transformed, so that from that time onwards he has to hide his face with a veil. Moses assembles the Israelites and repeats to them the commandments he has received from Yahweh, which are to keep the Sabbath and to construct the Tabernacle. "And all the construction of the Tabernacle of the Tent of Meeting was finished, and the children of Israel did according to everything that Yahweh had commanded Moses", and from that time Yahweh dwelt in the Tabernacle and ordered the travels of the Israelites.