Exodus 32:4-6

4He took what they handed him and made it into an idol cast in the shape of a calf, fashioning it with a tool. Then they said, “These are your gods, Israel, who brought you up out of Egypt.”

5When Aaron saw this, he built an altar in front of the calf and announced, “Tomorrow there will be a festival to the Lord.”

6So the next day the people rose early and sacrificed burnt offerings and presented fellowship offerings. Afterward they sat down to eat and drink and got up to indulge in revelry.