Jamieson, Fausset and Brown on Isaiah 11:14

14. With united forces they shall subdue their foes (Am 9:12).

fly--as a bird of prey (Ha 1:8).

upon the shoulders--This expresses an attack made unexpectedly on one from behind. The image is the more apt, as the Hebrew for "shoulders" in Nu 34:11 is used also of a maritime coast ("side of the sea": Hebrew, "shoulder of the sea," Margin). They shall make a sudden victorious descent upon their borders southwest of Judea.

them of the east--Hebrew, "children of the East," the Arabs, who, always hostile, are not to be reduced under regular government, but are only to be despoiled (Jr 49:28, 29).

lay ... hand upon--take possession of (Da 11:42).

Edom--south of Judah, from the Dead Sea to the Red Sea; "Moab"--east of Jordan and the Dead Sea.

Ammon--east of Judea, north of Moab, between the Arnon and Jabbok.