from
Easton's 1897 Bible Dictionary
Erastus
beloved. (1.) The "chamberlain" of the city of Corinth (Rom.
16:23), and one of Paul's disciples. As treasurer of such a city
he was a public officer of great dignity, and his conversion to
the gospel was accordingly a proof of the wonderful success of
the apostle's labours.
(2.) A companion of Paul at Ephesus, who was sent by him along
with Timothy into Macedonia (Acts 19:22). Corinth was his usual
place of abode (2 Tim. 4:20); but probably he may have been the
same as the preceding.