Erastus is probably cited as the most influential Christian in Corinth at the time. He was the city treasurer at Corinth. A Latin inscription has been discovered which states ‘Erastus laid this pavement at his own expense in appreciation of his appointment as aedile'. The aedile was appointed for one year and was responsible for the city streets and buildings, and for certain finances. It must be seen as quite likely that a city treasurer (oikonomos) would be appointed to such a post. That Paul was associated with the city treasurer would add greatly to his standing in some Roman eyes. Erastus was a common name, so this is probably not the Erastus mentioned in Acts 19:21-22. Quartus is otherwise unknown. That he is the only one in the list of greetings to be called ‘the brother' may suggest that he was in fact Erastus' genuine brother, or it may simply indicate that he was a Christian.
Related Commentaries of Romans 16:23
Romans 16:23-24
23 Gaius mine host, and of the whole church, saluteth you. Erastus the chamberlain of the city saluteth you, and Quartus a brother.
24 The grace of our Lord Jesus Christ be with you all. Amen.