Deuteronomy 21:2-4

Darby Translation

² then thine elders and thy judges shall go forth, and they shall measure unto the cities which are round about him that is slain;

³ and the city that is nearest unto him that is slain, even the elders of that city shall take a heifer that hath not been wrought with, that hath not drawn in the yoke;

⁴ and the elders of that city shall bring down the heifer unto an ever-flowing watercourse, which is not tilled, nor is it sown, and shall break the heifer's neck there in the watercourse;