Why didn't Adam and Eve find a talking snake to be strange? Why didn't they think it odd that the serpent spoke?

TL;DR:

Whether Adam and Eve did not know better, were used to animals speaking, or were used to spirits speaking, Adam and Eve apparently did not find the talking snake to be strange. What was strange is that Adam and Eve believed the lies of the talking snake over the truth God spoke.

what does the bible say?

Genesis 3:1–7 depicts the interaction between Eve and the serpent, where the serpent cunningly questions God's command about the tree of knowledge. Eve engages in conversation with the serpent, perhaps suggesting that animals speaking was not unusual in their context. Though not explicitly stated in the Bible, the possibility of animals having speech abilities is raised, supported by instances like Balaam's donkey speaking truth. The New Testament references the deception of Eve by the serpent, highlighting the ongoing relevance of this narrative. This story underscores humanity's susceptibility to deception and sin, as seen in Adam and Eve's choice to believe the serpent over God, echoing a pattern seen today. Despite the fall, Jesus' sacrifice offers redemption and triumph over sin, restoring the broken relationship between humanity and God.

from the old testament

Genesis 3:1–7 records a conversation between the serpent and Eve. Verses 1–3 read: “Now the serpent was more crafty than any other beast of the field that the Lord God had made. He said to the woman, ‘Did God actually say, “You shall not eat of any tree in the garden”?’ And the woman said to the serpent, ‘We may eat of the fruit of the trees in the garden, but God said, “You shall not eat of the fruit of the tree that is in the midst of the garden, neither shall you touch it, lest you die.”’”
Adam and Eve were innocent—and they did not have the same kind of experience of animals that we have today (Genesis 9:2). Adam and Eve were created alongside the animals and given dominion over them (Genesis 1:28), but there was no curse until after their sin (Genesis 3). After God rescued Noah and his family, He renewed the blessing to "be fruitful and multiply and fill the earth" (Genesis 9:1), but now "the fear of you and the dread of you shall be upon every beast of the earth and upon every bird of the heavens, upon everything that creeps on the ground and all the fish of the sea. Into your hand they are delivered" (Genesis 9:2).
We all know, from childhood, that if an animal opens its mouth and begins speaking to us, that would be extremely strange, and even frightening. But it is possible that all the animals were originally given the power of speech. The Bible doesn't explicitly say this, but from the way that Eve reacted to the serpent, it seems the fact that he spoke was a natural and normal thing to her. That being said, Balaam did not seem distressed that his donkey spoke, and instead was upset that the donkey had made him look foolish (Numbers 22:28–30).
Whether or not animals have ever had the power of speech, there are powerful beings (God, angels, Satan, demons) who can manipulate the physical world, including enabling animals to speak. For instance, "the LORD opened the mouth of [Balaam's] donkey" to speak to him after the donkey had seen the angel of the LORD and moved (Numbers 22:21–35). Clearly Balaam's donkey spoke truth whereas the serpent's speech was intended for deception.

from the new testament

Eve talking to the snake is not recorded in the New Testament, but his deceiving her is (2 Corinthians 11:3).

implications for today

Satan is often referred to as a serpent, or a dragon. Many believe that Satan was possessing the serpent in Eden so as to speak to Eve without raising suspicion. More strange than talking to a snake is that despite walking with God daily in a perfect Paradise, Eve was deceived into distrusting God, and both Adam and Eve took the fruit (Genesis 3:6–7; Romans 5:12). When the serpent contradicted God and made it seem that God was holding something back from Adam and Eve, they believed the serpent instead of believing their Creator (Genesis 3:1–7).

Today, men and women everywhere are making the same mistake. They are turning away from God, who loves them and made them, and listening to the words of a crafty deceiver who calls God into question. This is what the Bible calls sin—the self-destructive impulse to choose darkness over light, to believe lies instead of truth, and to accept what is unhealthy and harmful while distrusting what brings us peace and joy (John 3:19; Romans 3:23; 6:23; James 1:14–18). Our first parents were deceived in this way, and we are all stained and cursed by their fall (Romans 5:12). However, just as Adam's sin threw the human race into chaos, Jesus' sacrifice was provided so that all who wish to be with God do not have to be separated from Him any longer (Romans 5:15–21). Satan triumphed for a temporary time, but Jesus' triumph is eternal.

"And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses, by canceling the record of debt that stood against us with its legal demands. This he set aside, nailing it to the cross. He disarmed the rulers and authorities and put them to open shame, by triumphing over them in him" (Colossians 2:13–15).

understand

The narrative in Genesis 3:1–7 portrays a conversation between Eve and the serpent, highlighting the serpent's cunning nature and its manipulation of Eve's understanding of God's command regarding the Tree of Knowledge of Good and Evil.
Eve and Adam did not seem to find it strange for animals to speak, perhaps suggesting a different context where such communication might have been normal or even expected.
The possibility of animals having the power of speech is considered, supported by biblical instances like Balaam's donkey speaking truth. This raises questions about the manipulation of the physical world by powerful beings like God, angels, Satan, or demons, emphasizing the importance of discerning truth from deception.

reflect

Have you ever been in a situation where something seemed normal to you but was perceived as strange or unusual by others? How did that experience shape your understanding of perception and reality?
Reflecting on the story of Adam and Eve, what are some instances in your life where you have been tempted to believe a lie over the truth, despite knowing what is right?
How do you reconcile the idea of innocence with the capacity to discern between truth and deception, especially in light of the biblical narrative of Adam and Eve?

engage

How does the concept of innocence influence our perception of what is normal or unusual in different contexts, both in biblical narratives and in our everyday lives?
In what ways do you think societal norms and cultural experiences shape our understanding of truth and deception, and how can we guard against being misled?
Considering the role of powerful beings like God, angels, Satan, or demons in manipulating the physical world, how do we discern between genuine spiritual experiences and deceptive influences in our lives?