Deuteronomy 27:4

2It shall be on the day when you shall pass over the Jordan to the land which the LORD your God gives you, that you shall set yourself up great stones, and coat them with plaster.

3You shall write on them all the words of this law, when you have passed over, that you may go in to the land which the LORD your God gives you, a land flowing with milk and honey, as the LORD, the God of your fathers, has promised you.

4It shall be, when you have crossed over the Jordan, that you shall set up these stones, which I command you today, on Mount Ebal, and you shall coat them with plaster.

5There you shall build an altar to the LORD your God, an altar of stones. You shall not use any iron tool on them.

6You shall build the LORD your God’s altar of uncut stones. You shall offer burnt offerings on it to the LORD your God.