[3:23] 1 tn The καί (kai) is epexegetical/explanatory (or perhaps resumptive) of the commandment(s) mentioned in the preceding verse.
[3:23] 2 tn This verse begins with the phrase καὶ αὕτη ἐστίν (kai {auth estin; cf. the similar phrase in 3:11 and 1:5), which is explained by the following ἵνα (Jina) clause, “that we believe in the name of his Son Jesus Christ.” The ἵνα thus introduces a clause which is (1) epexegetical (explanatory) or (2) appositional. By analogy the similar phrase in 3:11 is also followed by an epexegetical ἵνα clause and the phrase in 1:5 by an epexegetical ὅτι (Joti) clause.
[3:23] sn His commandment refers to what follows – the commandment from God is to believe in his Son, Jesus Christ, and to love one another.
[3:23] 3 sn The author of 1 John repeatedly attributes the commandments given to believers as given by God the Father, even though in John 13:34-35 it was Jesus who gave the commandment to love one another. 2 John 4-5 also attributes the commandment to love one another directly to the Father. Thus it is clear that God the Father is the subject of the verb gave here in 3:23.
[5:2] 4 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.”
