The second thing of interest is the Greek word translated as “fellow workers.” This is a single compound Greek word containing the preposition “with” and the Greek word for Worker, which is the same Greek word from which we get our word for “energy.” This particular word is used only here by John but is often used by Paul to speak of those who were working with him in the cause of the Gospel. Consider some of the people whom Paul calls his fellow workers: Prisca and Aquila (Rom. 16:3), Urbanus (Rom. 16:9), Timothy (Rom. 16:21), Titus (2 Cor. 8:23), Epaphroditus (Philip. 2:25), Clement (Philip. 4:3), Jesus (not Jesus Christ) and Justus (Col. 4:11), Philemon (Philemon 1:1), and Aristarchus, Demas, and Luke (Philemon 1:24).
However, here, John is saying that if we help and support those who have gone out for the sake of the Gospel, then we have become co-workers with them in the truth. In God’s perspective, those who go and those who supply are both workers in the truth. When we support missionaries and workers in the Gospel, we are not simply supporting them or donating to their cause; we are actually co-working with them in the truth. This ought to change the way we view missions, missionaries, and our participation with them by supporting them in their work. When we support them, then we too are participating with them in the work. By giving, we too have become workers.
David Robison