These were the four major Philistine cities of that day.
# will be abandoned ... will turn into a devastation
These two phrases mean the same thing and emphasize the complete destruction of these cities. (See: [[rc://en/ta/man/translate/figs-parallelism]])
# They will drive out Ashdod at noon
Here "They" refers to the enemies of the Philistines. Possible meanings for "at noon" are 1) the enemies will defeat Ashdod before noon or 2) the enemies will attack Ashdod at noon while the people are resting and unaware.
# they will uproot Ekron
The defeat of Ekron is spoken of as if it was a tree that was pulled from the ground and thrown away. AT: "they will take the people of Ekron away as if uprooting a tree" (See: [[rc://en/ta/man/translate/figs-metaphor]])
# the inhabitants of the seacoast, the nation of the Kerethites
The first phrase explains where the Kerethites lived.
# Canaan, land of the Philistines
The Philistines were one of several people groups who lived in Canaan.
# until no inhabitant remains
"until no one is left." This can be stated in positive form. AT: "until every inhabitant is dead"