When Sin Entered the World
Thinking about Romans 5:12.
Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men, because all sinned— (Romans 5:12)
Paul has just been discussing the blessings of the reconciled in the Lord Jesus Christ (Romans 5:10-11).
Romans 5:12-21 is a summary of Paul’s case for righteousness by faith.
The section which now follows [Romans 5:12-21] summarizes the situation facing all people. “In Adam” there is only condemnation and (spiritual) death, and “in Christ” there is acquittal and life eternal. A person is “in Christ” through faith (not because faith is meritorious!), and without faith in Christ he is “in Adam.” “In Adam” is the man who stands on his own performance and apart from faith. “In Adam” is “out of Christ.” To be “in Adam” is to be represented by Adam and to be “in Christ” is to be represented by Christ. - McGuiggan, Romans, 162
Through one man sin entered the world.
Clearly, this is talking about Adam and what happened in the Garden of Eden in Genesis 3. Sin entered or was introduced into this world through one man - through Adam.
Paul mentions in Romans 5:14 that Adam “is a type of Him who was to come” - speaking of Jesus Christ.
Death entered the world through sin.
There is a lot of debate among biblical commentators about whether the death Paul has in mind here is spiritual or physical death.
Certainly, physical death is a consequence of sin (Genesis 3:19). But also, spiritual death (separation from God) is also a consequence of sin (Isaiah 59:1-2).
I think spiritual death is primarily what Paul has in mind here (although physical death is included in the consequences of sin) because he is showing a contrast between Adam and Jesus. He emphasizes that in Jesus there is eternal life (Romans 5:17-18, 21).
Death spread to all men because all sinned.
As I mentioned in a previous article, I don’t believe the Scriptures teach that we inherit Adam’s sin or that we are born sinners.
So to be consistent with other biblical passages (like Ezekiel 18:20) that teach we don’t inherit the guilt of our forefather’s sin - how should we interpret this phrase in Romans 5:12?
I believe this phrase can be interpreted to mean: “Spiritual death spread to all men because all men have committed sin.” It’s not that all have become sinners by inheriting Adam’s guilt, but that all have become sinners by committing sin (1 John 3:4).