1 Samuel 5:4 - Matthew Poole's English Annotations on the Holy Bible

The head is the seat of wisdom; the hands, the instruments of action: both are cut off, to show that he had neither wisdom nor strength to defend himself nor his worshippers. This the priests, by concealing Dagon's shame before, make it more evident and infamous. Only the stump of Dagon, Heb. only Dagon, i.e. that part of it from which it was called Dagon, to wit, the fishy part, for dag in Hebrew signifies a fish. And hence their opinion seems most probable, that this idol of Dagon had in its upper parts a human shape, and in its lower parts the form of a fish; for such was the form of divers of the heathen gods, and particularly of a god of the Phoenicians, (under which name the Philistines are comprehended,) as Diodorus Siculus and Lucian both witness, though they call it by another name. Was left to him, or, upon it, i.e. upon the threshold; there the trunk abode in the place where it fell, but the head and hands being violently cut off, were flung to distant and several places.