Heshbon. See on ch. 15:4.
Sibmah. This city was assigned to Reuben (Num. 32:37, 38; Joshua 13:15, 19) and was famous for its grapes (Jer. 48:32). The vines of this beautiful and prosperous country were destroyed by the cruel invaders. The city of Sibmah was near Heshbon, its location uncertain. The figure of the branches of Moabite grapevines reaching out in various directions probably suggests the places to which the product of its vines was exported, in the form of raisin cakes.
Unto Jazer. That is, the branches of the flourishing vine of Heshbon and Sibmah reached northward even unto Jazer, a city on the northern frontier (west or northwest of Rabbath-ammon), originally in Gilead (Num. 32:1, 3, 35; 2 Sam. 24:5; 1 Chron. 26:31). They stretched eastward into the Arabian Desert, and westward they crossed the Dead Sea to reappear on the slopes of En-gedi (S. of Sol. 1:14). The words of Isaiah picture the flourishing and extensive vineyards of Heshbon and Sibmah as constituting a single vine reaching out in all directions (see Jer. 48:32).