Who are the “children”, “fathers” and “young men” addressed in 1 John 2?

Question

2 My little children, I am writing these things to you so that you may not sin. ...

12 I am writing to you, little children, because your sins are forgiven for his name's sake.
13 I am writing to you, fathers, because you know him who is from the beginning. I am writing to you, young men, because you have overcome the evil one. I write to you, children, because you know the Father.
14 I write to you, fathers, because you know him who is from the beginning. I write to you, young men, because you are strong, and the word of God abides in you, and you have overcome the evil one.

18 Children, it is the last hour, and as you have heard ...

28 And now, little children, abide in him...

1 John 2 - ESV

Who are the "little children"? In verse 2, 8, and 28 it seems to be the members of the church, but verse 12-14 suggests otherwise because "young men" and "fathers" are also addressed. Why does John address these three groups? Do they all represent the church? If not, who do they represent?

Answer 1

Addressing the children is what builds the frame of his counsel. Fathers and young man come in between. Later on, ch. 3 of the letter, he extends and explains the concept of children for all insofar as all are children of the one Father.

Interesting that even in this letter he does not explicitly address women as he does fathers and young men. Those for whom the author is a father, be they men or women, old or young, accepted his addressing of children for themselves.

Answer 2

I would suggest that, based on John's style in 1 John, 2:18 starts a new pericope where 12-14 are part of the immediately preceding pericope. Where the age divisions in 12-14 could be different groups within the church (probably Ephesus), in verse 18 I see John gently asserting his eldership (not in a rude, authoritarian way). "Children" (verse 18) is a vocative/nominative, and prefer vocative since it fits the context a bit better since he is directly addressing them. He's giving a specific message to them about the proper understanding of Jesus as both fully God and fully human.