Matthew Poole and continuators on 1 Samuel 5:4

4 And when they arose early on the morrow morning, behold, Dagon was fallen upon his face to the ground, before the ark of the LORD, and the head of Dagon, and both the palms of his hands were cut off upon the threshold, onely the stump of Dagon was left to him .

The head is the Seat of Wisdom; the Hands, the Instruments of Action: both are cut off, to shew that he had neither Wisdom nor Strength to Defend himself, nor his worshippers. Thus the Priests by concealing Dagon's shame before, make it more evident and infamous.

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 an 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.

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 slung to distant and several places.

Marginal references: Or, the fishy part.