Numbers 34:12 (BSB)

Then the border will go down along the Jordan and end at the Salt Sea. This will be your land, defined by its borders on all sides.”

From Numbers 34. Also in the ESV.

Commentary on Numbers 34:12

• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Numbers 34:12: And the border shall go down to Jordan,.... A well known river to the east of the land of Canaan: and the goings out of it shall be at the salt sea; the sea of Sodom; and though all sea water is generally salt, this was remarkably so, through the great quantity of bitumen and nitre in it; hence it was called Asphaltites; thus as...
• Keil & Delitzsch (Lutheran), Biblical Commentary on the Old Testament on Numbers 34:10-12: Num 34:10-12 The Eastern Boundary. - If we endeavour to trace the upper line of the eastern boundary from the fountain-place just mentioned, it ran from Hazar-enan to Shepham, the site of which is unknown, and “from Shepham it was to go down to Riblah, on the east of Ain” (the fountain).