Somehow Onesimus, perhaps through a third person, was brought into Paul's house and he heard the good news of the gospel and became a Christian. Now, that changes everything because this was a man who was a thief. This was a man who was starting to learn how to live positively in a negative world. Perhaps none of us have had the problems that this man had, because he knew that if he went back to Colossae to face his master he could be punished severely. However, something else has happened in the meantime. Philemon has also heard the good news. Now we believe that Philemon probably heard the gospel at Ephesus, and we can assume that a number of years have passed between when Onesimus ran away and when Paul led him to Christ in Rome. During that time Philemon has traveled the 100 miles from Colossae to Ephesus, where Paul in Acts chapter 19 spent two and a half years telling people about the positive word of God. Philemon became a Christian, went back to the Colossae and became a part of the local church in that city, which met in a house because church buildings were not in vogue until probably 200 years or more later. So there are those two situations. Onesimus becomes saved in Rome and Philemon became saved probably in Ephesus and has gone back home.