Romans 5:12-13

Wherefore This refers to all the preceding discourse, from which the apostle infers what follows: he does not therefore make a digression, but returns to speak again of sin and righteousness; as if he had said, “We may from these premises infer, that the benefit which we believers receive from Christ is equal to the detriment we derive from Adam; yea, is on the whole greater than that.” For, as by one man That is, Adam, the common father of the human species; (he is mentioned, and not Eve, as being the representative of mankind;) sin entered into the world Actual sin, namely, the transgression of Adam and its consequence, a sinful nature, which took place in him, through his first sin, and which he conveyed to all his posterity; and death With all its attendants. It entered into the world when it entered into being; for till then it did not exist; by sin Therefore it could not enter in before sin; and so Namely, by one man; death passed From one generation to another; upon all men, for that all have sinned Namely, in Adam, their representative, and as being in his loins. That is, they are so far involved in his first transgression and its consequences, and so certainly derive a sinful nature from him, that they become obnoxious to death. Instead of, for that, Dr. Doddridge renders εφ ' ω, unto which, (namely, unto death, mentioned in the preceding clause,) all have sinned. In which ever way the expression is rendered, the words are evidently intended to assign the reason why death came upon all men, infants themselves not excepted. For until the law For, from the fall of Adam, unto the time when God gave the law by Moses, as well as after it; sin was in the world As appeared by the continual execution of its punishment; that is, death: but It is a self- evident principle that sin is not, and cannot be, imputed where there is no law Since the very essence of sin consists in the violation of a law. And consequently, since we see, in fact, that sin was imputed, we must conclude that the persons, to whose account it was charged, were under some law. Now this, with respect to infants, could not be the law of nature, (any more than the law of Moses,) for infants could not transgress that; it must therefore have been the law given to Adam, the transgression whereof is, in some sense, imputed to all, even to infants, he being the representative of all his posterity, and they all being in his loins. In other words, they do not die for any actual sins of their own, being incapable, while in infancy, of committing any, but through Adam's sin alone.