The group addressed as little children can best be taken to comprise the congregation as a whole, not a certain age group. A positive argument for this interpretation is the use of the term little children in 1 John 2.1 (which see). A negative one is this: if the author had intended an age group parallel to that of “the fathers” and “the young men,” one would expect another sequence, namely, children, young men, fathers.

For I am writing see 2.1. In verses 12-13b John uses the present tense of “to write,” in verses 13c and 14 the aorist tense; the latter may be rendered also “I have written” (New English Bible). This variation is probably a matter of style rather than meaning.

Because (here and in the five next sentences): the Greek conjunction can mean either “because” or “that.” Many versions (among them Revised Standard Version, Good News Translation) have “because,” but “that” seems to be more probable, since John is stressing some vital truths of Christian life. To do so he can better be understood as repeating what he has said than as saying why he has said it.

For your sins are forgiven, see comments on 1.7 and 9. The perfect tense indicates a situation in the present that is the result of an event or act in the past. The implied agent is God, not Christ.

For his sake is in the Greek literally “because of his name.” For “name” see comments on 3.23. The pronoun refers to Jesus Christ; hence, for example, ‘on Jesus Christ’s account,’ ‘because of what Jesus Christ did.’

A literal rendering of the Greek expression is to be avoided in many receptor languages, because it would make the expression unintelligible. It may also be misleading, for example, because it suggests that the pronouncing of Jesus Christ’s name has a magic effect.

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 .