¹ tn Once more there is the familiar difficulty of determining whether the phrase refers (1) to what precedes or (2) to what follows. Here, because ἐν τούτῳ (en toutw) is followed by a clause introduced by ὅταν (Jotan) which appears to be related, it is best to understand ἐν τούτῳ as referring to what follows. The following ὅταν clause is epexegetical to ἐν τούτῳ, explaining how we know that we love God’s children: “by this we know that we love God’s children, whenever we love God and keep his commandments.”

² tn After a verb of perception (the participle ὁ πιστεύων [Jo pisteuwn]) the ὅτι (Joti) in 5:5 introduces indirect discourse, a declarative or recitative clause giving the content of what the person named by the participle (ὁ πιστεύων) believes: “that Jesus is the Son of God.” As in 4:15, such a confession constitutes a problem for the author’s opponents but not for his readers who are genuine believers.