Jerome refers to Doctor Lucas Medicus Antiochensis, that is Dr. Luke of Antioch. Certainly Luke, who traveled widely, writes in much detail of Antioch and seems to have spent some time there. It would seem however that Luke's home at the time he met Paul, was in Philippi, then a chief city of Macedonia, and a Roman Colony. (Acts 16:12)
Paul the Apostle mentions him in his letter to the Colossians 4:14 as Luke the Beloved Physician. In Luke's writings, (Luke and Acts) he makes use of specific medical terms for illnesses. His general writings speak much of his learning. Theologians who have studied Luke's writings comment on his scientific and historic accuracy, in his references to places and people. Disputed points that have been used against Luke have in recent years been found to have been verified.
Souter suggests from the references in 2 Corinthians 8:18 and 12:18 that Luke may well have been the brother of Titus. Certainly we know that Luke became Paul's personal physician and close friend. A careful reading of Luke's account of their shipwreck on the island of Malta would indicate that Luke practiced medicine during their 3 month stay on the island.
In Acts 28:8 we read of the Governor of the Island, Publius, whose father was dying of an advanced case of 'fever and dysentery' as the Revised version accurately translates Luke's Greek text. This disease is still a problem in Malta and has many times been fatal there. Paul and Luke go to see him, and Luke who diagnoses the disease, steps aside as Paul lays hands on the old man and prays for instant healing. The people recognized this instantaneous miracle, and Luke uses the Greek word 'iaomai' that portrays the immediacy of the healing.
In the next verse, Luke speaks of many Islanders then approaching them, and of their being treated, and healed. Here the word Luke uses is 'therapeuo' which speaks of therapy, or treatment of diseases. He goes on to relate that the people 'tim-e' (tee-may) that is paid them for this medical treatment. So here we have a missionary doctor practicing medicine while Paul was actively praying and ministering the Word to the people. So successful was this partnership that when the winter was over, they were supplied with all their needs as they journeyed on to Rome.
Paul in 2 Timothy 4:11 recounts the devotion and continued care of Luke for himself as he approached his execution. It is probable the Luke practiced medicine in Rome to support their needs, during the long time of Paul's imprisonment.
Sometimes we get to take care of, and support a ministry leader; and thereby fill a much needed ministry opportunity for the Kingdom of God.