Deuteronomy 3:8

8 We took the land at that time out of the hand of the two kings of the Amorites who were beyond the Jordan, from the valley of the Arnon to Mount Hermon;

Deuteronomy 3:8 Meaning and Commentary

Deuteronomy 3:8

And we took at that time out of the hands of the two kings of
the Amorites
Sihon king of Heshbon, and Og king of Bashan;

the land that [was] on this side Jordan;
where Moses then was, being in the plains of Moab, and was the country beyond Jordan, with respect to the land of Canaan, and when in that:

from the river of Arnon unto Mount Hermon;
Arnon was a river which divided Moab and the Amorites, ( Numbers 22:13 ) and Hermon was a mountain of Gilead, which ended where Lebanon began, and was the northerly border of this country. It was remarkable for the dew that fell on it; (See Gill on Psalms 133:3).

Deuteronomy 3:8 In-Context

6 We utterly destroyed them, as we did to Sihon king of Heshbon, utterly destroying every inhabited city, with the women and the little ones.

7 But all the cattle, and the spoil of the cities, we took for a prey to ourselves.

8 We took the land at that time out of the hand of the two kings of the Amorites who were beyond the Jordan, from the valley of the Arnon to Mount Hermon;

9 ([which] Hermon the Sidonians call Sirion, and the Amorites call it Senir;)

10 all the cities of the plain, and all Gilead, and all Bashan, to Salecah and Edrei, cities of the kingdom of Og in Bashan.