Erastus appears here and in two other places in the New Testament (Acts 19.22 and Rom 16.23, where he is identified as the city treasurer). It is possible that these verses are referring to the same person. In the Acts passage we are told that Paul sent Erastus and Timothy ahead to Macedonia, while he, Paul, stayed on in Asia for a while.

Corinth is a city in Greece. In 27 B.C. it became the capital of the province of Achaia (see the map, page 6|fig:Map_Paul-12.jpg). The book of Acts informs us that Paul founded the church there during his second missionary journey (see Acts 18.1-18).

Trophimus is perhaps the same Ephesian Christian mentioned twice in the book of Acts: as a companion of Paul (together with Timothy) on his journey to Jerusalem (Acts 20.4, 5), and as the cause of Paul’s problems with the mob in Jerusalem, who thought that Paul had brought a Gentile into the temple (Acts 21.29).

Miletus was an important port city in the Aegean Sea, south of Ephesus. It is mentioned twice in the book of Acts (20.15, 17). It was there where Paul met with the Ephesian church leaders for the last time.

Quoted with permission from Arichea, Daniel C. and Hatton, Howard A. A Handbook on Paul’s Second Letter to Timothy. (UBS Handbook Series). New York: UBS, 1995. For this and other handbooks for translators see here .