Adam Clarke on Numbers 24:24

Ships shall come from the coast of Chittim - Some think by Chittim the Romans, others the Macedonians under Alexander the Great, are meant. It is certain that the Romans did conquer the Assyrians, including all the people of Syria, Mesopotamia, etc., but Calmet strongly contends that by Chittim Macedonia is meant, and that the prophecy refers to the conquests of Alexander. Chittim was one of the sons of Javan, the son of Japheth, the son of Noah, Gen 10:4; and his posterity, according to Josephus, Antiq., 1. iii., c. 22, settled in Cilicia, Macedonia, Cyprus, and Italy also; and therefore, says Mr. Ainsworth, the prophecy may imply both the troubles that befell the Assyrians and Jews by the Greeks and Seleucidae, in the troublous days of Antiochus.

And shall afflict Eber - Probably not the Hebrews, as some think, but the people on the other side the Euphrates, from עבר abar, to pass over, go beyond; all which people were discomfited, and their empire destroyed by Alexander the Great.