1 John 2:4

2:4 The one who says “I have come to know God” ¹  and yet does not keep his commandments is a liar, and the truth is not in such a person.

1 John 3:23

3:23 Now ²  this is his commandment: ³  that we believe in the name of his Son Jesus Christ and love one another, just as he gave ⁴  us the commandment.

[2:4]  ¹ tn Grk “know him.” See the note on the phrase “know God” in 1 John 2:3 for explanation.

[3:23]  ² tn The καί (kai) is epexegetical/explanatory (or perhaps resumptive) of the commandment(s) mentioned in the preceding verse.

[3:23]  ³ 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]  ⁴ 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.