en_tn/1jn/02/13.md

I am writing to you, fathers

The word "fathers" here is possibly a metaphor referring to mature believers. Alternate translation: "I am writing to you, mature believers" (See: rc://en/ta/man/jit/figs-metaphor)

you know

"you have a relationship with"

the one who is from the beginning

"the one who has always lived" or "the one who has always existed." It refers either to "Jesus" or to "God the Father."

young men

This possibly refers to those who are no longer new believers but are growing in spiritual maturity. Alternate translation: "young believers" (See: rc://en/ta/man/jit/figs-metaphor)

overcome

The writer is speaking of the believers' refusal to follow Satan and of their frustrating his plans as if it were a matter of conquering him. (See: rc://en/ta/man/jit/figs-metaphor)