1 tn Grk “that I hear”; the ἵνα (Jina) clause indicates content. This is more smoothly expressed as an English infinitive.
2 tn Grk “walking in (the) truth” (see the note on the phrase “living according to the truth” in 3 John 3).
3 sn Clearly the author does not refer to himself alone by the use of the first person plural pronoun we here, since the issue is support for the traveling missionaries. It stands in contrast to the pagans mentioned in the previous verse, and is thus to be understood as inclusive of all true Christians: the author, Gaius, and all true Christians. All true Christians ought to support the endeavors of these traveling missionaries in their efforts to counteract the heretical teaching of the opponents.
4 tn The ἵνα (Jina) clause indicates the result of such support for the traveling missionaries: The Christian who helps to support them in their efforts thus becomes a coworker in cooperation with the truth. Although the dative τῇ ἀληθείᾳ (th alhqeia) is somewhat difficult to specify, it would appear (corresponding to the σύν- [sun-] prefix of the noun modified) to indicate a sense of cooperation with “the truth” which is at work through the missionaries. There is precedent in the Johannine literature for understanding “truth” as personified (John 8:32, “the truth will make you free”; possibly also 1 John 3:19). More explicitly, 1 John 4:6 identifies the Holy Spirit as “the Spirit of Truth,” a characterization repeated in 1 John 5:6. Thus it seems likely that the “truth” at work through the missionaries here is ultimately the Holy Spirit, who works through their efforts. The Christian who supports them thus becomes a coworker with the Spirit of God himself.