Exodus 18:12

12And Jethro, Mosesfather-in-law, brought a burnt offering and sacrifices to God; and Aaron came with all the elders of Israel to eat bread with Mosesfather-in-law abefore God.

Exodus 24:4

4And bMoses 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 cpillars, according to the twelve tribes of Israel.
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