Numbers 31:2-6

MLV(i) 2 Avenge the sons of Israel of the Midianites. Afterward you will be gathered to your people. 3 And Moses spoke to the people, saying, Arm men from among you* for the war, that they may go against Midian, to execute Jehovah's vengeance on Midian. 4 From every tribe a thousand, throughout all the tribes of Israel, you* will send to the war.
5 So there were delivered, out of the thousands of Israel, a thousand of every tribe, twelve thousand armed for war. 6 And Moses sent them, a thousand of every tribe, to the war, them and Phinehas the son of Eleazar the priest, to the war, with the vessels of the sanctuary and the trumpets for the alarm in his hand.