It is a good idea to make a break at the end of verse 16 and begin a new sentence here, as Good News Translation does. And it should be made clear that this verse is a summary statement of the territory assigned to all three tribes: Reuben, Gad, and East Manasseh. So this verse may start with “On the west the territory of the three tribes extended to….”

The Arabah: see 1.1.

Chinnereth: this is Lake Galilee (Good News Translation) or the Sea of Galilee (most English translations). In areas where lakes are unknown, we may express “Lake Galilee” as “a small fresh water sea named Galilee.”

The sea of the Arabah, the Salt Sea: today it is known as the Dead Sea.

Under the slopes of Pisgah on the east: this is not easy to understand. New Jewish Publication Society’s Tanakh makes “the slopes of Pisgah” the eastern boundary. Mount Pisgah is about 15 kilometers (9 miles) east of the northern end of the Dead Sea. Here the name may refer to the mountain itself, or more likely to the whole mountain range, of which Mount Nebo was the summit (32.49; 34.1). It is recommended that Good News Translation be followed here: “and to the foot of Mount Pisgah on the east.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on Deuteronomy. (UBS Helps for Translators). New York: UBS, 2000. For this and other handbooks for translators see here .