And he: the Greek pronoun he is emphatic. It has the force of “someone with the qualities just indicated.” To bring this out one may say ‘and this one’ or ‘now it is he who.’
He is the expiation for our sins: the Greek verbal noun originally served to express the act of expiating, but in the present verse it refers either (1) to the person who expiates, or (2) to the means used in expiating. The Greek translation of the Old Testament, taking it in the latter sense, uses it for “sin offering,” or “atoning sacrifice” (Ezek 44.27, compare Num 5.8). Interpretation (1) and (2) seem to be equally acceptable. For our sins, or ‘the sins we do,’ see comments on 1.7.
Several restructurings of the clause are possible. In case (1) one may shift to ‘he (or Jesus Christ) expiates our sins.’ In case (2) the best form of the clause may be ‘he (or, Jesus Christ) is the means by which our sins are expiated,’ or, with a further shift, ‘through him God expiates our sins,’ or perhaps ‘Jesus Christ is the sin offering that causes our sins to be expiated.’
† The Greek term rendered expiation (here and 4.10) is derived from a verb which outside the New Testament generally means “to pacify,” namely, an offended deity. Another meaning of the verb, rarer in non-Christian writers, is to perform an act by which ritual or moral defilement is removed. In the Greek and Hellenistic world it was believed that the prescribed rituals (which might or might not include the slaughter of animals) could serve, so to speak, as a powerful disinfectant. Every one who had performed this ritual could be confident that the taint, the defilement, was removed.
In the Greek Old Testament the verb in question is the most general term for such rituals. Almost invariably it has the sense “to cleanse from defilement.” Where priests or other men are the ones who expiate, it refers to sacrifices or purifying rites. But in Hebrew thought it is also possible (as it never is among the Greeks) that God performs the action.
Accordingly the meaning of the Greek verb comes close to that of “to cleanse” (see 1.7 and comments) and “to forgive” (see 1.9 and comments). An interpretation along these lines leads to renderings like “Christ himself is the means by which our sins are forgiven” (Good News Translation), ‘who makes good all our sins,’ ‘it is he who is what-frees-from our sins’ (making use of a term that in the indigenous religion refers to the exorcising of magical influences), ‘he is the means of the disappearance of our sins,’ ‘he himself takes away sin,’ ‘he covers up our sins.’ The last mentioned rendering is fully acceptable in some languages (among them probably also Hebrew, for “to cover” is one of the meanings the corresponding Hebrew verb can have), but in other languages and cultures it would suggest hiding (so that God cannot see it), and therefore cannot be used.
And not for ours only but also for the sins of the whole world, literally ‘not for ours only, but also for the whole world,’ a construction made possible by the fact that the Greek verb in question can take as goal either ‘the sin (of a man)’ or ‘the man (who sins).’ The two phrases may better be rendered as one or two full sentences; for example, ‘He covers up our sins, and also the sins of the whole world,’ ‘And not only our sins he makes up for. He makes up also for the sins of the whole world.’
The phrase the whole world may be rendered ‘all those who live on this earth,’ ‘men from everywhere’ (in a language that only possesses terms for a small geographic area), or simply “all men” (Good News Translation). For the noun see also comments on 2.15, meaning (3).
Quoted with permission from Haas, C., de Jonge, M. and Swellengrebel, J.L. A Handbook on The First Letter of John. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .