1 John 2:9

2:9 The one who says he is in the light but still hates ¹  his fellow Christian ²  is still in the darkness.

1 John 4:20

4:20 If anyone says ³  “I love God” and yet ⁴  hates his fellow Christian, ⁵  he is a liar, because the one who does not love his fellow Christian ⁶  whom he has seen cannot love God whom he has not seen. ⁷ 

1 John 3:12

3:12 not like Cain ⁸  who was of the evil one and brutally ⁹  murdered his brother. And why did he murder him? Because his deeds were evil, but his brother’s were righteous.

[2:9]  ¹ tn Grk “the one saying he is in the light and hating his brother.” Here καί (kai) has been translated as “but” because of the contrast present in the two clauses.

[2:9]  ² tn Grk “his brother.” Here the term “brother” means “fellow believer” or “fellow Christian” (cf. BDAG 18 s.v. ἀδελφός 2.a). In the repeated uses of this form of address throughout the letter, it is important to remember that sometimes it refers (1) to genuine Christians (those who have remained faithful to the apostolic eyewitness testimony about who Jesus is, as outlined in the Prologue to the letter, 1:1-4; an example of this usage is 2:10; 3:14, 16), but often it refers (2) to the secessionist opponents whose views the author rejects (examples are found here at 2:9, as well as 2:11; 3:10; 3:15; 3:17; 4:20). Of course, to be technically accurate, in the latter case the reference is really to a “fellow member of the community”; the use of the term “fellow Christian” in the translation no more implies that such an individual is genuinely saved than the literal term “brother” which the author uses for such people. But a translation like “fellow member of the community” or “fellow member of the congregation” is extremely awkward and simply cannot be employed consistently throughout.

[4:20]  ³ tn Grk “if anyone should say…”

[4:20]  ⁴ tn “Yet” is supplied to bring out the contrast.

[4:20]  ⁵ tn See note on the phrase “fellow Christian” in 2:9.

[4:20]  ⁶ tn See note on the phrase “fellow Christian” in 2:9.

[4:20]  ⁷ 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.

[3:12]  ⁵ sn Since the author states that Cain…was of the evil one (ἐκ τοῦ πονηροῦ, ek tou ponhrou), in the immediate context this imagery serves as an illustration of 3:8a: The person who practices sin is of the devil (ἐκ τοῦ διαβόλου, ek tou diabolou). This is similar to John 8:44, where Jesus told his opponents “you people are from your father the devil…[who] was a murderer from the beginning.” In both Jewish and early Christian writings Cain is a model for those who deliberately disbelieve; Testament of Benjamin 7:5 looks forward to the punishment of those who “are like Cain in the envy and hatred of brothers.” It is not difficult to see why the author of 1 John used Cain here as a model for the opponents in light of their failure to “love the brothers” (see 1 John 3:17).

[3:12]  ⁶ tn For the Greek verb σφάζω (sfazw) L&N 20.72 states, “to slaughter, either animals or persons; in contexts referring to persons, the implication is of violence and mercilessness – ‘to slaughter, to kill.’” As a reflection of this nuance, the translation “brutally murdered” has been used.