Exodus 24:4

4And aMoses wrote down all the words of the Lord. He rose early in the morning and built an altar at the foot of the mountain, and twelve bpillars, according to the twelve tribes of Israel.

Joshua 8:30-31

Joshua Renews the Covenant

30At that time Joshua built an altar to the Lord, the God of Israel, con Mount Ebal, 31just as Moses the servant of the Lord had commanded the people of Israel, as it is written in the Book of the Law of Moses, “an altar of uncut stones, upon which no man has wielded an iron tool.” And they offered on it burnt offerings to the Lord and sacrificed peace offerings.

1 Kings 18:31-32

31Elijah took twelve stones, according to the number of the tribes of the sons of Jacob, to whom the word of the Lord came, saying, dIsrael shall be your name,” 32and with the stones he built an altar in the name of the Lord. And he made a trench about the altar, as great as would contain two seahs
A  seah was about 7 quarts or 7.3 liters
of seed.
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