isaiah 11:14 But they shall fly upon the shoulders of the Philistines toward the west; they shall spoil them of the east together: they shall lay their hand upon Edom and Moab; and the children of Ammon shall obey them. - Free Bible Online

      14. With united forces they shall subdue their foes (Am 9:12).
      fly--as a bird of prey (Hab 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 (Jer 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.

JFB.