What does 1 Corinthians 16:19 mean?

Paul turns from commending Stephanas to his fellow Corinthians to sending greetings from others. His greetings from the churches of "Asia" may refer to a region that would have included Ephesus and the surrounding area. It's possible that Paul is emphasizing once more that the church in Corinth is only one among the larger world of Christian churches. He would like them to see themselves as belonging to that larger body and not making up church practices for themselves as they go along.

Paul also sends "hearty greetings" from Aquila and Prisca and their house church. This Christian couple, often better known as Aquila and Priscilla, lived in Corinth for a while, and they have an interesting story. Scholars suggest their Latin names may indicate they were freed slaves. They were forced to leave Rome in AD 49 when the emperor Claudius banned all the Jewish people from that city (Acts 18:1–2). Their career as tent-makers allowed them to settle and set up shop in Corinth, where Paul found them. Also a tentmaker, Paul joined his efforts to theirs and lived with them while establishing the church in Corinth (Acts 18:3).

When Paul left to go to Ephesus, Aquila and Prisca went with him. Their hearty greeting in the Lord to the Corinthians was for people they knew well and likely missed as much as Paul did. Later, the couple moved back to Rome after the ban on Jews had been lifted (Romans 16:3) before moving back to Ephesus again (2 Timothy 4:19).