Numbers 21:13-14

13From there they set out and camped on the other side of the Arnon, which is in the wilderness that extends from the border of the Amorites, for the aArnon is the border of Moab, between Moab and the Amorites. 14Therefore it is said in the Book of the Wars of the Lord,

Waheb in Suphah, and the valleys of the Arnon,
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