Original sin is one of those topics that divide Christians. Those of us who believe in it profess that it’s essential to Jesus’ saving mission. It’s the reason why we need to be “born again” to “see the kingdom of God” (John 3:3). Those who reject original sin might say it’s not fair for God to punish us for something we didn’t do—or they might just call it “stupid,” or refuse to believe it because they don’t see it as part of God’s revelation.
The Council of Trent defined original sin as “the death of the soul.” The Catechism of the Catholic Church reaffirmed this definition (403) and added a key nuance: original sin is called sin “only in an analogical sense: it is a sin ‘contracted’ and not ‘committed’—a state and not an act” (404).
The biblical text that the Magisterium has appealed to as evidence for this belief is Romans 5:12: “Therefore as sin came into the world through one man and death through sin, and so death spread to all men because all men sinned.” The Council of Trent appeals to this verse in its Decree Concerning Original Sin. The Catechism of the Catholic Church appeals to it, too, along with Romans 5:18-19, in its teaching that original sin is a consequence of Adam’s sin for all of humanity (402).
But where does the Magisterium get off interpreting Romans 5:12 as a reference to original sin?
We can start by making a simple either-or statement: Paul has to be talking about either personal sin or original sin. (Personal sin means the sins we commit ourselves, whether they’re venial or mortal.) Now, if we can show that it’s not personal sin, then it would follow that he’s talking about original sin.
How might we establish that Paul is not talking about personal sin?
Well, consider this question: which members of the human race can’t possibly be guilty of personal sin? Clearly, one answer is infants. Another is the severely mentally handicapped. So if we can show that infants and the severely mentally handicapped must be numbered among the “all” who sinned, then it will follow that Paul is thinking of original sin.
The key for proving that infants and the severely mentally handicapped must be numbered among the “all” is the connection that Paul makes between death and sin: “death spread to all men because all men sinned.” Notice that Paul draws a parallel between the “all” that constitutes the group who “have sinned” and the “all” that constitutes the group to whom “death spread.” Moreover, Paul sees the death that extends to all as an effect of the sin that extends to all.
Do infants and the severely mentally handicapped die? Yes.
Given the parallel between the two groups, it follows that infants and the mentally handicapped are included within the category of “all have sinned.” And if that’s the case, then Paul is not thinking of personal sin here; he’s thinking of original sin.
Now, someone might counter, “If we say that whoever dies is included within the category of ‘all have sinned,’ then we must say that Jesus and Mary would have to be included there because they both died (or at least Jesus, if we want to say Mary didn’t die). But to say that Jesus and Mary are included in the “all have sinned” category is absurd.
In response, this would be true if and only if we didn’t have a source of knowledge other than Jesus’ and Mary’s humanity for knowing that they were exceptions to the rule.
For example, we can say it belongs to the nature of a human being as a corporeal being—a being with a mortal body—to die. So when I, knowing this, observe that Aristotle has died, I can reasonably infer that Aristotle is a corporeal being.
But suppose that it’s revealed that God will preserve Aristotle (or, we might argue, Elijah or Enoch) from death. Given that he doesn’t die, must I conclude that he’s not a corporeal being? Of course not. I know that he still belongs to the category of corporeal beings, even though he doesn’t die, because I have something other than Aristotle’s nature for determining whether he will die: God’s revelation.
Similarly, although death belongs to those who have contracted the sin of Adam by nature, it doesn’t follow that Jesus and Mary must have contracted the sin of Adam by nature because they died. The reason is that we have something other than Jesus’ and Mary’s death and human nature for determining whether they have contracted Adam’s sin: God’s revelation.
But we don’t have any such revelation when it comes to infants and the severely mentally handicapped. This being the case, the death that they experience is seen as evidence for being included among the group “all have sinned,” because Paul clearly teaches that death extends to all as an effect of the type of sin that he’s speaking of.
Given that infants and the severely mentally handicapped are included in Paul’s category of “all have sinned,” and we know that such members of the human race in principle cannot commit personal sin, it follows that in Romans 5:12, Paul is thinking about original sin and not personal sin.
There’s another line of argumentation that we can use here.
Consider that the “all have sinned” refers to either a) every human being, including those humans who can’t sin personally, like infants and the severely mentally handicapped, or b) only human beings who have committed personal sin.
Now, if Paul is referring only to humans who have committed personal sin, then such people would be included within the category of “all have sinned” by imitation of Adam. But if that’s the case, then death would extend only to those who commit personal sin, since Paul clearly teaches that death extends to all who are included within the category “all have sinned”: “death spread to all men because all men sinned.” Surely, death doesn’t extend only to those who commit personal sin. Infants and the severely mentally handicapped also die.
Therefore, the “all have sinned” cannot refer only to human beings who have committed personal sin; it must refer to every human being, including those humans who can’t personally sin. And it follows that personal sin is not Paul’s target here in Romans 5:12. Rather, his target is original sin.
Original sin is not just something that we infer from the craziness of sin that we see on our nightly cable news channels. It’s part and parcel of God’s revelation. And it’s not just bad news. It’s part and parcel of the Christmas message: “for to you is born this day in the city of David a Savior, who is Christ the Lord” (Luke 2:10-11). What did we need to be saved from? That’s right: original sin.