Romanos 16:23

Gaius my host, and of the whole church, saluteth you. Erastus the treasurer of the city saluteth you, and Quartus the brother.

This Gaius is doubtless that Gaius whom Paul baptized with his own hands (1 Corinthians 1:14), and in whose house he was a guest when Romans was written. Gaius appears here as a man of considerable means and great hospitality, being called a "host of the whole church." This could be understood to mean that his doors were continually open to Christians from many places, or that the congregation actually met in his house, as the church met in the house of Prisca and Aquila; and it could quite easily mean both these things. Gaius quite evidently requested Paul to include his greetings to the Roman Christians, some of whom, perhaps, had been partakers of his hospitality.

Erastus was the treasurer of the city of Corinth, being therefore a man of consequence and power in that metropolis. Not many of his station in life accepted and obeyed the gospel; but it is refreshing to know that Erastus was an exception. A person, or persons, bearing this name were mentioned in Acts 19:22,2 Timothy 4:20; but there is no certainty, either that those references are to the same person, or that either of them refers to the treasurer of Corinth.

Quartus the brother ... is here mentioned alongside the treasurer of the city, and with the same dignity and tenderness. The community of love in Christ was actually operating under a whole new set of value judgments which counted all people, rich and poor, weak and powerful, wise and foolish, learned or unlearned, bond or free, Jews or Gentile - all people one in Jesus Christ.