A Bastard. The word (mamzer) occurs in Deuteronomy 23:2 (3, Hebrew), where it may possibly mean "a stranger." It is generally considered to signify one whose birth has a blemish in it—one born of incest or adultery.
In Deuteronomy the LXX. renders, ἐκ πόρης, "one of harlot birth;" here, ἀλλογενής, "foreigner." The Vulgate has separator, which is explained as meaning either the Lord, who as Judge divides the just from the unjust, or the Conqueror, who divides the spoil and assigns to captives their fate.
Here it doubtless signifies "a bastard race"; a rabble of aliens shall inhabit Ashdod, which shall lose its own native population. The Targum explains it differently, considering that by the expression is meant that Ashdod shall be inhabited by Israelites, who are deemed "strangers" by the Philistines.
Ashdod (see note on Amos 1:8). The pride. All in which they prided themselves. This sums up the prophecy against the several Philistine cities. Their very nationality shall be lost.