Romans 16:23

Yet another fellow-laborer, but of a wholly different kind: he is Paul's host, under whose roof he is composing this work. This Gaius can neither be the Gaius of Derbe in Asia Minor, Acts 20:4, nor the Gaius of a church in the neighborhood of Ephesus, 3 John 1:1. He is evidently the person of whom Paul speaks 1 Corinthians 1:14, one of the first believers of Corinth whom he had baptized with his own hand before the arrival of Silas and Timothy. Paul calls him at once his host and that of the whole church. These last words might signify that when the church of Corinth held a full meeting (1 Corinthians 14:23), it was at the house of Gaius that these assemblies took place. But there attaches to the term ξένος, host, rather the idea of welcome given to strangers. Paul means, therefore, no doubt that the house of Gaius is the place of hospitality by way of eminence, that which at Corinth is ever open to receive Christian strangers. From Gaius, the first member of the church of Corinth named here, the apostle naturally passes to two other distinguished Christians of the same church, and who had personal relations to some of the Christians of Rome. Erastus, occupying an exalted post in the administration of the city (probably as treasurer), cannot be the evangelist of this name mentioned Acts 19:22; he is more likely the person of whom Paul speaks 2 Timothy 4:20. We know nothing of Quartus.

One sees, then, that all these persons are placed with the order, tact, and discernment which never failed the apostle, even in the minutest details of his letters.