Numbers 21:13,26
From there they removed, and pitched on the other side of Arnon, which is in the wilderness that comes out of the coasts of the Amorites: for Arnon is the border of Moab, between Moab and the Amorites.
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Numbers 22:36
And when Balak heard that Balaam was come, he went out to meet him to a city of Moab, which is in the border of Arnon, which is in the utmost coast.
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Deuteronomy 2:24,36
Rise you up, take your journey, and pass over the river Arnon: behold, I have given into your hand Sihon the Amorite, king of Heshbon, and his land: begin to possess it, and contend with him in battle.
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Deuteronomy 3:8,16
And we took at that time out of the hand of the two kings of the Amorites the land that was on this side Jordan, from the river of Arnon to mount Hermon;
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Joshua 12:1
Now these are the kings of the land, which the children of Israel smote, and possessed their land on the other side Jordan toward the rising of the sun, from the river Arnon to mount Hermon, and all the plain on the east:
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