Exodus 32:3-7

So all the people tore off the gold rings which were in their ears and brought them to Aaron.

Then he took the gold from their hands, and fashioned it with an engraving tool and made it into a cast metal calf; and they said, “This is your god, Israel, who brought you up from the land of Egypt.”

Now when Aaron saw this, he built an altar in front of it; and Aaron made a proclamation and said, “Tomorrow shall be a feast to the Lord.”

So the next day they got up early and offered burnt offerings, and brought peace offerings; and the people sat down to eat and to drink, and got up to engage in lewd behavior.

Then the Lord spoke to Moses, “Go down at once, for your people, whom you brought up from the land of Egypt, have behaved corruptly.