If evolution is true, then there was death before Adam. Yet the Bible teaches that the result of sin is death. Therefore, there could have been no death before sin, right?
Actually, no that is not right, and it is not what the Bible teaches.
Such a question confuses two different kinds of death.
It is apparent that the Bible teaches two different types of life and two different corresponding types of death. There is physical life that ends with physical death, and there is a spiritual life that the Bible calls eternal life. Those who do not have eternal life are spiritually dead.
This is not a questionable teaching. There is no other way to interpret a passage like Ephesians 2:1-3, which says we were all once dead in our trespasses and sins.
Notice that Ephesians 2 doesn't say that we all shall die because of our trespasses and sins. We all were dead in our trespasses and sins. Jesus brought us to life, if we are disciples, by his grace.
This is the death that is tied to sin. It is a spiritual death; an absence of eternal life.
Paul says something similar in Romans 8:13. There he says that those who live according to the flesh will die. There he is talking to Christians, those who have already been buried with Christ in baptism and raised to the new life of Christ. They are not currently dead in their trespasses and sins because they have been given life by Christ.
Paul tells those disciples that if they live according to the flesh, they will die. Of course, this can't mean physical death because they're going to die a physical death whether they live according to the flesh or not. That verse goes on to say, "If, by the Spirit, you put to death the deeds of the body, then you will live."
Again, this can't mean physical death because we're all going to die physically whether they mortify the deeds of the body or not. Paul was not unaware of that.
If sin is tied to that eternal life, then the Gospel has nothing to do with whether or not there was physical death before Adam.
Again, this makes sense, because in the story, Adam is told by God that he will die "in the day that he eats of [the fruit]." Of course, we know that Genesis goes on to say that Adam lived 930 years after eating of the fruit!
But the New Testament continually teaches that all men, Adam and all his descendants, have been dead in sins ever since until being delivered by the grace of God provided in Jesus Christ. Adam died spiritually "in the day" that he ate of the fruit, not physically. It is spiritual death that is the result of the fall, not physical death.
Admittedly, the story of the Garden of Eden, as found in Genesis 2 and 3, tells us that there was no death before the Garden. In fact, according to the story, in complete contradiction to Genesis 1, there's no anything before the Garden. There's not only no death before the Garden, there's no life, either. According to Genesis 2, all the animals were formed from the ground of the Garden of Eden, and they were formed after man, not before.
Is this a contradiction? It's only a contradiction for those that hold the idea that a story about two people named Man and Life—living in a garden planted by God with a talking, walking snake and two trees that can confer life and divine knowledge of good and evil upon humans—is actual history. Does that story really sound like it's even trying to be literal history?
Eighteen centuries ago, long before Charles Darwin was born and before anyone had any idea that the earth could be billions of years old—in fact, before anyone had a word for "billion"—a Christian wrote:
Augustine, the famous Christian theologian and bishop of the African city of Hippo in the late 4th and early 5th centuries, said that all Christians acknowledge that the stories of the Old Testament are symbolic. With that acknowledge, they then need to ask which ones are also historically accurate.
We're gotten hung up on literal words, but the early churches weren't. They still knew that the only real proof of the Gospel is the power of God that transforms lives, creates love, and silences all critics by its fruit.
I've addressed all that in a different faq, so I won't repeat it here.
Suffice it to say that there is nothing about the story of the Garden of Eden that requires it to be literal. If it were literal, it would contradict Genesis 1. It is a symbolic story about why man is spiritually dead in his trespasses and sins.
Thus, whether there was death before Adam has nothing whatsoever to do with the Gospel, because sin is tied to spiritual death, not physical death.