He (God) helps, a city of the Amorites on the east of Jordan, and assigned, with neighbouring places in Gilead, to Gad (Num. 32:1, 35; Josh. 13:25). It was allotted to the Merarite Levites (21:39). In David’s time it was occupied by the Hebronites, i.e., the descendants of Kohath (1 Chr. 26:31). It is mentioned in the “burdens” proclaimed over Moab (Isa. 16:8, 9; Jer. 48:32). Its site is marked by the modern ruin called Sar or Seir, about 10 miles west of Amman, and 12 from Heshbon. “The vineyards that once covered the hill-sides are gone; and the wild Bedawin from the eastern desert make cultivation of any kind impossible.”
Jaazer
Jaazer, also spelled Jazer, was a town east of the Jordan that Israel met on the way to the promised land. In Numbers 21, “Moses sent to spy out Jaazer,” and Israel took its villages. Later the tribes of Reuben and Gad saw that it was “a place for cattle” and asked to settle there. Gad rebuilt it, and Joshua 21 lists Jazer among the cities given to the Levites. It is a small name, but it shows how the land was won, then shared out, one town at a time.
6 verses
Numbers
And Moses sent to spy out Jaazer, and they took the villages thereof, and drove out the Amorites that were there.
Now the children of Reuben and the children of Gad had a very great multitude of cattle: and when they saw the land of Jazer, and the land of Gilead, that, behold, the place was a place for cattle;
Ataroth, and Dibon, and Jazer, and Nimrah, and Heshbon, and Elealeh, and Shebam, and Nebo, and Beon,
And Atroth, Shophan, and Jaazer, and Jogbehah,
Joshua
And their coast was Jazer, and all the cities of Gilead, and half the land of the children of Ammon, unto Aroer that is before Rabbah;
Heshbon with her suburbs, Jazer with her suburbs; four cities in all.
From Easton's Bible Dictionary
Matthew George Easton, 1897