Numbers 23:29

Revised Standard Version (RSV-CI)

And Balaam said to Balak, “Build for me here seven altars, and provide for me here seven bulls and seven rams.”

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And because God helped the Levites who were carrying the ark of the covenant of the Lord, they sacrificed seven bulls and seven rams.

So Balak took Balaam to the top of Peor, that overlooks the desert.

And Balak did as Balaam had said, and offered a bull and a ram on each altar.