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Gen. 3:14 And the LORD God said unto the serpent, Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life:
Critics say that this verse offers a herpetological inaccuracy, saying that snakes do not eat dirt. In my view, it is enough to point out that snakes do take particles into their mouths on their tongues to "taste" the air. That's their sense of smell, and if this isn't "eating dirt" literally, it certainly is figuratively!
In fact, though, the sense probably is figurative: The idea of eating dust is associated with abject humiliation elsewhere - cf. Ps. 72:9 ("They that dwell in the wilderness shall bow before him; and his enemies shall lick the dust."), Is. 49:23 ("And kings shall be thy nursing fathers, and their queens thy nursing mothers: they shall bow down to thee with their face toward the earth, and lick up the dust of thy feet") and especially Mic. 7:17 ("They shall lick the dust like a serpent".)
I should add that the word here, "lick," was not unknown (it is used in Numbers), but the word "eat" was chosen as a poetic counterpoint to the profession of Adam and Eve that they did "eat" of the tree.