Deuteronomy 21:2

Revised Standard Version (RSV-CI)

then your elders and your judges shall come forth, and they shall measure the distance to the cities which are around him that is slain;

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“If in the land which the Lord your God gives you to possess, any one is found slain, lying in the open country, and it is not known who killed him,

and the elders of the city which is nearest to the slain man shall take a heifer which has never been worked and which has not pulled in the yoke.