Note 7 at Ro 16:23: The name Gaius was a common Roman name. This name is used five times in Scripture (Ac 19:29, 20:4; here; 1Co 1:14; and 3Jo 1) and refers to at least three different men.

Ac 19:29 refers to Gaius as being a man of Macedonia (see note 1 at Ac 16:9), while Ac 20:4 refers to a Gaius who was of Derbe (see note 5 at Ac 14:6), a city of Asia (see note 3 at Ac 16:6).

It is probable that the Gaius referred to here was the same man that Paul mentioned in 1Co 1:14, since the book of Romans was written from Corinth (see Life for Today Study Bible Notes, Introduction to Romans, Date and Place of Writing). This would make Gaius one of the few people in Corinth that Paul actually baptized. This verse says that Gaius was not only Paul's host, but also host of the whole church, implying that he had a house church meeting in his residence.

The Apostle John addressed the epistle of 3 John to Gaius. Some speculate that this man was the same Gaius that Paul was referring to here.

Note 8 at Ro 16:23: The name Erastus is mentioned three times in Scripture (Ac 19:22, this verse, and 2Ti 4:20). Erastus means "beloved" (Strong's Concordance).

Most scholars agree that this was the same Erastus that Paul sent with Timothy into Macedonia (see note 1 at Ac 16:9) while Paul remained in Ephesus (see note 3 at Ac 18:19). Paul later wrote to Timothy that Erastus abode in Corinth (2Ti 4:20), while this verse reveals that he was the chamberlain of that city (see note 9 at this verse).

Note 9 at Ro 16:23: The word "chamberlain" is only used six times in the Bible (2Ki 23:11; Es 2:3, 14-15; Ac 12:20; and here). Of the two times this word is used in the New Testament, Ac 12:20 uses "chamberlain" in the sense of an eunuch who keeps the king's bedchamber, and in this verse, it was referring to Erastus being the treasurer of the city of Corinth.

Note 10 at Ro 16:23: The name Quartus means "fourth" (Strong's Concordance). This is the only mention of Quartus in Scripture. He was a Christian brother in Corinth who sent greetings to the saints in Rome.