The children of Israel camped in the wilderness. Moses' wife and his two sons, together with Jethro, his father-in-law, came to see him there. Jethro, seeing how Moses was overburdened with the care of so many people, advised him to appoint officers over them, under himself, who might attend to all their smaller concerns.
God Himself had the chief government of the people and on Mount Sinai, where Moses spoke to Him and saw His great glory, He gave to them, not only the Ten Commandments, but many other laws and directions, for all they should do in worshiping Him.
It was a sight when God spoke to Moses on Mount Sinai! There was thunder and lightening, and a thick cloud, like the smoke of a furnace, about the mountain. There was a great voice of a trumpet, sounding louder and louder so Moses went up and spoke with the Lord God.
Moses spent forty days in the mount, and the people began to wonder what had become of him. They asked Aaron to make them some images which they might worship, and that might guide them out of the wilderness. Aaron knew there was only one God, yet he did as the people desired.
He told them to bring their golden ornaments to him. He then melted them, shaped the metal into the form of a calf (one of the false gods of the Egyptians), built an altar before it, on which the people might lay their offerings, and told them that was their god that had brought them out of the land of Egypt.
The next day the people offered sacrifice to this calf, just as the heathens, who did not know God, worshiped their idols, or false gods. God saw this and He was so displeased at their wickedness that He would have destroyed them all, had not Moses interceded for them. Moses returned from the mount to the camp, and asked Aaron how it was that he and the people had committed so great a sin.
Aaron tried to excuse himself by laying the blame on the unruly Israelites. But there was no excuse for him. Moses burnt the calf, ground it to a powder, and threw it into the water that supplied the camp.
God also, though he had granted Moses' prayer, commanded that great numbers of the people should be put to death for their sin.