Deuteronomy 27:5-7
5
And there shalt thou build an altar unto the LORD thy God, an altar of stones: thou shalt not lift up any iron tool upon them.
6
Thou shalt build the altar of the LORD thy God of whole stones: and thou shalt offer burnt offerings thereon unto the LORD thy God:
7
And thou shalt offer peace offerings, and shalt eat there, and rejoice before the LORD thy God.