Question:
What is the difference between Genesis 3:14 and Isaiah 65:25 about the serpent eating dust?
Answer:
Genesis 3:14 was a curse spoken against Satan, not against the serpent. Many had assumed that God cursed the serpent, making it a legless creature that eats dust—a very unusual interpretation!
A pattern God won't change, which Jesus also followed, “For with the same measure that you use, it will be measured back to you.” (Luke 6:38). Applying it to Satan, God justifiably assigned (symbolically) to him the serpent's characteristics ( belly crawling & eating of dust) spiritually. No, Satan did not become a real snake! The curse was a figure of speech.
"And the LORD God said unto the serpent...upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life." (Genesis 3:14)
Satan was lowered to the same status as that of the serpent! How, you ask? Since Satan used a serpent, God attached some of its physical aspects to him, but in a non-physical way. Here's how:
Satan is cursed more than any creature.
Satan is lowered, debased, and considered unclean, which is what "crawling on the belly" means. (See Psa 44:25; Lev 11:31)
Satan will experience loss and defeat, which is what the "eating of dust" means. (See Mic 7:17; Psa 72:9; 44:25 Isa 49:23)
Real serpents were created marvellously to crawl on their belly. They feed on smaller creatures, but occasionally, they may eat or lick dust with their forked tongues for smelling purposes, using special extrasensory glands located in their mouths. Dust isn’t their food, but it gets eaten whenever they clean their tongues after use!
This rules out the idea that serpents' physiology has changed after God cursed them!
Isaiah 65 is not exactly about animals; it is about human personalities. It uses a symbolic language to point to the spiritual conditions in the new Gentile Church.
To show the drastic changes in humans, it uses the analogy of serpents and wolves supernaturally changing their predatory eating habits, from eating prey to eating dust and grass. Likewise, those who were serpent-like and wolf-like will receive a new nature by being born of the Spirit. Their old nature will be gone!
These images pointed to God's new creation under the rule of Christ. (See Eph 4:20-24).
There is no conflict between Genesis 3:14 and Isaiah 65:25. The difference is subtle. In both accounts, it is the personalities behind the serpent that mattered. In Genesis, it was Satan who was demoted to a spiritual status as that of a serpent. In Isaiah, it’s the believer who is promoted to a new spiritual nature in Christ.