¹ tn Once again there is the problem (by now familiar to the interpreter of 1 John) of determining whether the phrase ἐν τούτῳ (en toutw) in 3:10 refers (1) to what precedes or (2) to what follows. If it refers to what precedes, it serves to conclude the unit which began with 2:28. The remainder of 3:10 would then form a transition to the following material (another “hinge” passage). On the other hand, if the phrase ἐν τούτῳ refers to what follows, then the entirety of 3:10 is a summary statement at the end of 2:28-3:10 which recapitulates the section’s major theme (conduct is the clue to paternity), and provides at the same time a transition to the theme of loving one’s brother which will dominate the following section (3:11-24). Although R. E. Brown (Epistles of John [AB], 416) prefers to see the phrase as referring to the preceding material, it makes better sense to refer it to the remainder of 3:10 that follows, and see the entirety of 3:10 as both a summary of the theme of the preceding section 2:28-3:10 and a transition to the following section 3:11-24.

² tn See note on the term “fellow Christian” in 2:9.

sn Does not love his fellow Christian. The theme of loving one’s fellow Christian appears in the final clause of 3:10 because it provides the transition to the second major section of 1 John, 3:11-5:12, and specifically to the following section 3:11-24. The theme of love will dominate the second major section of the letter (see 1 John 4:8).

³ tn Once again there is the problem of determining whether the phrase ἐν τούτῳ (en toutw) refers (1) to what precedes or (2) to what follows. This is the first of 5 uses of the phrase in the present section (4:9, 10, 13, 17; 5:2). In this case (as also in the next two instances) there is a ὅτι (Joti) clause following which is related and which explains (i.e., which is epexegetical to) the phrase ἐν τούτῳ. Thus the meaning here is, “By this the love of God is revealed in us: that God has sent his only Son into the world in order that we might live through him.”

⁴ tn In terms of syntax the force of the genitive τοῦ θεοῦ (tou qeou) may be (1) objective, (2) subjective, or (3) both. The phrase occurs for the first time in the letter in 2:5. Here in 4:9 the epexegetical ὅτι (Joti) clause which follows makes it clear that this is a subjective genitive, emphasizing God’s love for us rather than our love for God, because it describes God’s action in sending his Son into the world.

⁵ tn This phrase is best understood as the equivalent of a dative of sphere, but this description does not specify where the love of God is revealed with regard to believers: “in our midst” (i.e., among us) or “within us” (i.e., internally within believers). The latter is probable, because in the context the concept of God’s indwelling of the believer is mentioned in 4:12: “God resides (μένει, menei) in us.”

⁶ sn Although the word translated one and only (μονογενής, monogenhs) is often rendered “only begotten,” such a translation is misleading, since in English it appears to express a metaphysical relationship. The word in Greek was used of an only child (a son [Luke 7:12, 9:38] or a daughter [Luke 8:42]). It was also used of something unique (only one of its kind) such as the mythological bird called the Phoenix (1 Clement 25:2). From here it passes easily to a description of Isaac (Heb 11:17 and Josephus, Ant. 1.13.1 [1.222]) who was not Abraham’s only son, but was one-of-a-kind because he was the child of the promise. Thus the word means “one-of-a-kind” and is reserved for Jesus alone in the Johannine literature of the NT. While all Christians are children of God (τέκνα θεοῦ, tekna qeou), Jesus is God’s Son in a unique, one-of-a-kind sense. The word is used in this way in all its uses in the Gospel of John (1:14, 18; 3:16, 18).

⁷ tn Grk “if anyone should say…”

⁸ tn “Yet” is supplied to bring out the contrast.

⁹ tn See note on the phrase “fellow Christian” in 2:9.

¹⁰ tn See note on the phrase “fellow Christian” in 2:9.

¹¹ sn In 4:20 the author again describes the opponents, who claim to love God. Their failure to show love for their fellow Christians proves their claim to know God to be false: The one who does not love his fellow Christian whom he has seen cannot love God whom he has not seen.