In Romans 6:5b Paul commands the church in Rome to [g]reet my beloved Epaenetus, who was the first convert to Christ in Asia.
Epaenetus also belongs to circle of the dear friends of the apostle, who had come from Asia (many manuscripts read, Achaia), where he had been the first convert. Many exegetes indeed believe that the Greek word used here, aparché, refers to the point in time of his conversion. However, aparché actually refers to a traditional votive offering for a god or a first gift from the harvest to the Lord. When people presented such a votive offering, they did so in the service of their idol or the Lord. Therefore, Paul is writing in Romans 16:5b that Epaenetus is a votive offering of Asia (or Achaia) for Christ (eis Christon).
It is quite possible that the Christians in Asia or Achaia have specifically chosen to dedicate him to the service of Christ in Rome (for the time being). In 1 Corinthians 16:13–18 we see that Stephanas, who had visited Paul in Ephesus on behalf of Corinth, was also called an aparché of Achaia.1
5 Greet also the church in their house. Greet my beloved Epaenetus, who was the first convert to Christ in Asia.