And David and his men went up, and invaded the Geshurites, and the Gezrites, and the Amalekites: for those nations were of old the inhabitants of the land, as thou goest to Shur, even unto the land of Egypt.
Here is an account of David's actions while he was in the land of the Philistines, a fierce attack he made upon some remains of the devoted nations, his success in it, and the representation he gave of it to Achish. 1.
Commenting on 1 Samuel 27:8-12
And David and his men went up,.... From Ziklag, where they dwelt: and invaded the Geshurites; some of the old inhabitants of the land of Canaan, the remains of the Amorites, whose land was given to the half tribe of Manasseh, but could never be expelled; and therefore David had a just right to invade them, and, if he could, either expel or destroy them...
David . . . went up, and invaded the Geshurites--(See Jos 13:2). and the Gezrites--or the Gerizi [GESENIUS], (Jos 12:12), some Arab horde which had once encamped there. and the Amalekites--Part of the district occupied by them lay on the south of the land of Israel (Jdg 5:14; Jdg 12:15).