I was surprised at how often my interpretation of the key passage Romans 5:12-21 has changed over the past months in general, and with looking at my two sources (Tennant and Dubarle) in particular. Then recently I saw something on evanevodialogue that just about hit the spot for me:
[T]the effect of the comparison between the two epochal figures, Adam and Christ, is not so much to historicize the individual Adam as to bring out the more than individual significance of the historic Christ.
- WORD Biblical Commentary (James Dunn)
I personally think it is difficult, though not impossible, to make full sense of Romans 5:12-21 (hereafter referred to as "the passage"

) without there having been some kind of historical Adam.
Even so, I think the idea that this passage is communicating some kind of a spiritual "taint" that is transmitted biologically, that causes people to sin, isn't the best way to read this passage. That view seems to me to be too individualistic, too focused on "me" and "myself" and "my bloodline" (which after all is shared only with my siblings, and which will be again unique for my children). Rather, the passage speaks of the human solidarity in sin which is not necessarily (not even primarily) biological in nature.
An example I heard at dinner demonstrates the point. A reverend from my church was discussing how money these days is dirty, and he gave the example of when our church building was being built (or renovated). The church wanted to find their own engineer, but the local authorities would not give a proper building permit unless the church used an engineer who was on their approved list. The church found one, but he (like every other engineer on that list would have done) asked for "contingency money" - a special allowance in case the building process was disturbed by local gangsters demanding "protection fees".
So even the church building is tainted. We supplied money to local hoodlums, who would no doubt go on to use it for evil purposes. And why did
they start doing wrong things? Perhaps they had abusive parents; perhaps they fell in with the wrong crowd at school; perhaps our government has failed to provide equity for its citizens. And maybe the parents themselves had abusive parents; maybe the school had a wrong crowd because the discipline teachers were too lax; maybe the government is failing because Western exporters of democracy have failed to understand local sensitivities and adapt to them; and so on ... love may make the world go round but oftentimes it's our sin that holds us together.
And so our church sinned because of those local gangsters; they in turn sinned because of their parents and their government; they in turn sinned because of others; and all these sins are but small tributaries of the great roaring river of human sin that finds its head in Adam's first sin. In Adam all sinned just as all who drink from a river are, in some way, drinking from its head, no matter how far downstream they may happen to be.
No wonder that we cannot be saved on our own. It is not simply that there are switches in our head that have been thrown the wrong way from birth; it is that in today's society (or any other society man has ever known), you often cannot make a move without participating in someone else's sin. I cannot buy a pair of jeans without implicitly endorsing sweatshop labor; I cannot build a house without helping the local thugs. If the Lord marked our transgressions who could stand? The web of sin between man and man is so tightly knit that no man can ever untangle himself.
And yet from Christ, a great river of life flows that can wash away our guilt as individuals and that will one day cleanse human society of the great cobwebs of sin that so cover it.
Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all men, because all men sinned -- just as the result of one trespass was condemnation for all men, so also the result of one act of righteousness was justification that brings life for all men. For just as through the disobedience of the one man the many were made sinners, so also through the obedience of the one man the many will be made righteous. [Rom 5:12, 18, 19 NIV]