Lords - Seranim, a title used exclusively of the princes of the five Philistine cities. The title is probably of Phoenician origin.

J…

Five lords of the Philistines. —The princes of the Pentapolis: Gaza, Ashdod, Askelon, Gath, Ekron. The word rendered “lords” is ev…

[Namely], five lords of the Philistines
The places they were lords of were Gaza, Ashdod, Ashkelon, Gath, and Ekron; …

As the Israelites were a type of the church on earth, they were not to be idle and slothful. The Lord was pleased to try them by the remains of the…