Paul exhorted the Corinthians “not to go beyond what is written” (1 Cor 4:6). When it comes to some traditional Christian interpretations, however, we have not always followed Paul’s advice. Regarding the idea that the snake who deceived Adam and Eve was actually Satan, we would do well “not to go beyond what is written,” since nowhere does the Bible state that the serpent was Satan.
Genesis 3:1 clarifies that the serpent was an animal among others: “The serpent (nachash; נחשׁ) was craftier than all the other creatures of the field (hayat ha’sadeh; חית השׂדה).” In response to the serpent’s deception, God says, “Cursed are you more than all the livestock (behemah; בהמה) and more than all the creatures of the field (hayat ha’sadeh; חית השׂדה); on your belly you shall go, and dust (afar; עפר) you shall eat” (Gen 3:14). Since this curse functions in relation to the other animals, it is best to read the serpent as a literal snake. Isaiah recalls this curse in an end-time vision, in which the snake is just another animal: “The wolf and the lamb shall graze together; the lion shall eat straw like the ox, and dust (afar; עפר) shall be the serpent’s food” (Isa 65:25). Isaiah did well not to go beyond what was written in Genesis.
Paul corroborates Genesis’ description of the serpent as an animal, telling the Corinthians, “I am afraid that as the serpent (ophis; ὄφις) deceived Eve by his cunning, your thoughts will be led astray from a sincere and pure devotion to Christ” (2 Cor 11:3). Speaking to the church at Rome, Paul states, “The God of peace will soon crush Satan under your feet” (Rom 16:20). While this statement might remind us of God telling the serpent that Eve’s offspring “will bruise your head” (Gen 3:15), Paul’s language does not parallel the Greek version of Genesis 3:15. Paul says that God will “crush” (suntribo; συντρίβω) Satan, but the Septuagint translates the Hebrew “bruise” (shuph; שׁוף) in Gen 3:15 with τηρέω (teréo; “guard”). Rather than drawing on Gen 3:15, Paul recalls the Psalms’ description of God crushing the primordial dragon, Leviathan: “You crushed (suntribo; συντρίβω) the heads of the dragons (drakónton; δρακόντων) on the waters; you shattered the heads of the dragon” (Ps 74[73 LXX]:13-14). The Hebrew terms for “dragon” in these verses are תנינים (tanninim; “sea-monsters”) and “Leviathan” (לויתן), respectively.
To be sure, Satan is like the serpent in that, being a “liar” (pseustes; ψεύστης, see Jn 8:44), the devil tries to “tempt” (peiradzo; πειράζω, e.g., Matt 4:1; Mk 1:13; Lk 4:2; 1 Thess 3:5; Rev 2:10) and “lead astray” (planáo; πλανάω, Rev 12:9; 20:10; cf. 2 Cor 11:3). But these terms for Satan are not used of the serpent who “deceives” (apatao; ἀπατάω) in Eden (Gen 3:13 LXX). Based on the biblical evidence alone, to equate the serpent with Satan would be to “go beyond what is written” in Scripture.