Exodus 32:25-29

25Aaron had let the people get out of control, and they became an object of ridicule to their enemies. When Moses saw this,

26he stood at the entrance to the camp and said, “If you’re on the Lord’s side, come over here to me!” Then all the Levites gathered around him.

27He said to them, “This is what the Lord God of Israel says: Each of you put on your sword. Go back and forth from one end of the camp to the other, and kill your relatives, friends, and neighbors.”

28The Levites did what Moses told them, and that day about 3,000 people died.

29Moses said, “Today you are ordained as the Lord’s priests. God gave you a blessing today because each of you fought with your own sons and brothers.”