Deuteronomy 27:4-6

New International Version - UK

⁴ And when you have crossed the Jordan, set up these stones on Mount Ebal, as I command you today, and coat them with plaster. ⁵ Build there an altar to the Lord your God, an altar of stones. Do not use any iron tool on them. ⁶ Build the altar of the Lord your God with stones from the field and offer burnt offerings on it to the Lord your God.