Unto the serpent; or rather, this or that serpent, which, as was said before on Genesis 3:1, was no ordinary serpent, but a serpent acted and assisted by the devil; and therefore this sentence or curse is pronounced against both of them:
1. Against the serpent itself, which though an unreasonable creature, and therefore not subject to a law, and consequently not capable of guilt or sin, Romans 4:15, yet, being the instrument of the devil's malice, is rightly punished; as other beasts being abused by man's sin did suffer together with him, Exodus 32:20 Leviticus 20:15-16, not for their crime, but partly for the punishment, and partly for the benefit of man, who is their lord and owner, Psalms 8:6; for whose sake seeing they were made, it is not strange if they be punished for his use, that in their punishment man might have a demonstration of God's anger against sin, and a motive to repentance. See Poole on "Genesis 6:1", and following verses to Genesis 6:22. See Poole on "Genesis 7:1", and following verses to Genesis 7:24.
2. Against the devil, who is here principally intended, though as he lay hid in the body of the serpent which he possessed and used, so his curse is here mentioned under the cover of the serpent's curse, and under the disguise of such terms as properly and literally agree to the serpent, but are also mystically to be understood concerning the devil; with whom the Lord entertaineth no conference, as he did with Adam and Eve, whose sin was less than his, and whom God meant to bring to repentance; but immediately denounceth the curse against him, as one that sinned against much greater knowledge, and from far worse principles, not from mistake or misinformation, but from choice and rebellion, from hatred of God, and from mere envy and implacable malice against men. Because thou hast done this, deceived the woman, and tempted her to this sin, thou art cursed; or, shalt be from henceforth, both really and in the opinion of all mankind: or, be thou. Every beast of the field; as in other respects, so particularly in that which here follows; upon thy belly shalt thou go. If the serpent did so before the fall, what then was natural, is now become painful and shameful to it, as nakedness and some other things were to man. But it seems more probable that this serpent before the fall either had feet, or rather did go with its breast erect, as the basilisk at this day doth; God peradventure so ordering it as a testimony that some other serpents did once go so. And so the sense of the curse being applied to this particular serpent, and to its kind, may be this: Whereas thou hadst a privilege above other kinds of serpents, whereby thou didst go with erected breast, and didst feed upon the fruits of trees and other plants; now thou shalt be brought down to the same mean and vile estate with them, upon thy belly (or rather, breast, as the word also signifies) shalt thou go, & c. as they do; and dust shalt thou eat. Dust is the food, as of earthworms, scorpions, and some other creatures, so also of some serpents, as appears both from Isaiah 65:25 Micah 7:17, and from the testimony of Nicander, Theriac, ver. 372, and Philo, an Arabic writer. Or, the dust is the serpent's sauce rather than his meat; whilst creeping and grovelling upon the earth, and taking his food from thence, he must necessarily take in dust and filth together with it. These two clauses being applied to the devil, signify his fall from his noble state and place to earth and hell; the baseness of his nature and of his food, his delight being in the vilest of men and things, it being now his meat and drink to dishonour God and destroy mankind, and promote the esteem and love of earthly things.