Jamieson, Fausset and Brown on Ezekiel 25:16

16. cut off the Cherethims--There is a play on similar sounds in the Hebrew, hichratti cherethim, "I will slay the slayers." The name may have been given to a section of the Philistines from their warlike disposition (1Sa 30:14; 31:3). They excelled in archery, whence David enrolled a bodyguard from them (2Sa 8:18; 15:18; 20:7). They sprang from Caphtor, identified by many with Crete, which was famed for archery, and to which the name Cherethim seems akin. Though in emigration, which mostly tended westwards, Crete seems more likely to be colonized from Philistia than Philistia from Crete, a section of Cretans may have settled at Cherethim in South Philistia, while the Philistines, as a nation, may have come originally from the east (compare De 2:23; Jr 47:4; Am 9:7; Zep 2:5). In Ge 10:14 the Philistines are made distinct from the Caphtorim, and are said to come from the Casluhim; so that the Cherethim were but a part of the Philistines, which 1Sa 30:14 confirms.

remnant of--that is, "on the seacoast" of the Mediterranean: those left remaining after the former overthrows inflicted by Samuel, David, Hezekiah, and Psammetichus of Egypt, father of Pharaoh-necho (Jr 25:20).