John describes his relationship to the church in the words whom (plural) I love in the truth. ‘I’ is emphatic (egō). Perhaps he is casting a side glance at the heretics. Not only had they compromised the truth, but they were a proud and loveless lot. John’s declaration is in complete contrast. The Greek phrase translated in the truth (as in v. 3 and in 3 John 1) lacks the article. It could therefore be an adverbial expression rendered ‘whom I love in truth’ (RV, NEB; cf. 1 John 3:18), or ‘truly’, that is, ‘in all Christian sincerity’ (Plummer). But the context, with two subsequent references to the truth, with the article (1–2), surely justifies the RSV and NIV translation whom I love in the truth. It was the truth which bound John in love to this church, especially the truth about Christ in opposition to the ‘lie’ of the heretics (1 John 2:21–23). Nor was he alone in his love for them, for also all who know the truth (literally ‘have come to know’ it, perfect, egnōkotes) shared his love. ‘The communion of love is as wide as the communion of faith’ (Alford).

5 Dear friend, you are faithful in what you are doing for the brothers and sisters, f even though they are strangers to you. 6 They have told the church about your love. Please send them on their way in a manner that honors God. 7 It was for the sake of the Name that they went out, receiving no help from the pagans. 8 We ought therefore to show hospitality to such people so that we may work together for the truth.

If the first reason for entertaining travelling missionaries is that they are brothers whom we should honour for setting out for the sake of the Name, the second is the much more practical one that they have no other means of support. We must do for them what others will not do. An important principle lies buried here, namely that we Christians should finance Christian enterprises which the world will not, or should not be expected to, support. Indeed, we have an obligation (ought) to do so. There are many good causes which we may support; but we must support our brothers and sisters whom the world does not support. This is a good guiding principle in Christian giving. The third reason for entertaining and providing for travelling missionaries is that by so doing we work together for the truth. This may mean that we become ‘fellow workers in the truth’ (RSV), implying that we are co-operating with the missionaries and ‘so play our part in spreading the truth’ (NEB)

9 I wrote to the church, but Diotrephes, who loves to be first, will not welcome us. 10 So when I come, I will call attention to what he is doing, spreading malicious nonsense about us. Not satisfied with that, he even refuses to welcome other believers. He also stops those who want to do so and puts them out of the church.

To John the motives governing the conduct of Diotrephes were neither theological, nor social, nor ecclesiastical, but moral. The root of the problem was sin. Diotrephes … loves to be first or (RSV) ‘likes to put himself first’ (philoprōteuōn). He did not share the Father’s purpose that in all things Christ should have the supremacy (Col. 1:18, prōteuōn). Nor would he kowtow to ‘the elder’. He wanted the supremacy himself. He was ‘greedy of place and power’ (Findlay). He had not heeded the warnings of Jesus against ambition and the desire to rule (e.g. Mark 10:42–45; cf. 1 Pet. 5:3). His secret self-love erupted in the antisocial behaviour described in the next verse. Smith comments that ‘proagein (2 Jn. 9) and philoprōteuein denote two tempers which disturbed the Christian life of Asia Minor—intellectual arrogance and personal aggrandisement’.

Demetrius is well spoken of by everyone—and even by the truth itself. We also speak well of him, and you know that our testimony is true.

What is clear is that Demetrius is given an impressive threefold testimony (cf. 1 John 5:8). First, he is well spoken of by everyone. The perfect passive memartyrētai conveys the idea that the testimony which everybody has borne to Demetrius remains valid. Secondly, this testimony is confirmed by the truth itself. This can hardly be a reference to the Son or the Spirit, although each is ‘the truth’ (John 14:6; 1 John 5:6). It surely means rather that the Christian genuineness of Demetrius did not need human witness; it was self-evident. The truth he professed was embodied in him, so closely did his life conform to it. Then Demetrius had a third witness: We also speak well of him (martyroumen) with a present and continuing testimony. This again looks like the first person plural of authority, by which John is referring to himself (as in v. 9).