Numbers 21:13-15
13 They set out from there and camped alongside the Arnon, which is in the desert extending into Amorite territory. The Arnon is the border of Moab, between Moab and the Amorites.
14
That is why the Book of the Wars of the Lord says:
“. . . Waheb in Suphah and the ravines,
the Arnon
15
and the slopes of the ravines
that lead to the site of Ar
and lie along the border of Moab.”