John was an elderly man and their leader. He used this expression to show his love for them. It can be translated as "My dear children in Christ" or "You who are as dear to me as my own children." (See: [[rc://en/ta/man/translate/figs-metaphor]])
## these things I write ##
"I am writing this letter"
## But if anyone sins ##
This is something that is likely to happen. "But when anyone sins" (See: [[rc://en/ta/man/translate/figs-hypo]])
## we…us ##
In verses 1-3 these words refer to John and the people he was writing to. (See: [[rc://en/ta/man/translate/figs-inclusive]])
## an advocate with the Father ##
"someone who speaks to God the Father and asks him to forgive us"
## Jesus Christ the righteous one ##
"and that person is Jesus Christ, the only one who is perfect"
## He is the propitiation for our sin ##
"Jesus Christ voluntarily sacrificed his own life for us, so that as a result God forgives our sins" (UDB)
## By this we know that we know him, if we keep his commandments ##
The phrase "we know him" means "we have a relationship with him." This can be translated as "If we do what he tells us to do, then we can be certain that we have a good relationship with him."