Colossians 4:14

Luke, the beloved physician - This is generally supposed to be the same with Luke the evangelist. See the preface to the notes on this gospel. Some, however, suppose them to be different persons; because, where it is evident that Luke the evangelist is meant, he never has more than his simple name Luke; and because the apostle is supposed to intend a different person here, he adds, ὁ ιατρος ὁ αγαπητος, the beloved physician.

It is conjectured that Luke "the beloved physician" (the same as the Evangelist), may have first become connected with Paul in professionally attending on him in the sickness under which he labored in Phrygia and Galatia (in which latter place he was detained by sickness), in the early part of that journey wherein Luke first is found in his company (Ac 16:10; compare Note, see on Ga 4:13).

Luke, the beloved physician - This was undoubtedly the author of the Gospel which bears his name, and of the Acts of the Apostles. He is mentioned as the traveling companion of Paul in Act 17:10, and appears to have accompanied him afterward until his imprisonment at Rome see 2Ti 4:11. From Col 4:11, it is evident that he was not by birth a Jew, but was probably a proselyte. He is supposed to have been a native of Cyrene, and to have died in Achaia, soon after the martyrdom of Paul, at the advanced age of 84. See Rob. Cal. Art. Luke. He is here mentioned as a physician, and in his Gospel, and in the Acts , there are incidental evidences that he was acquainted with the science of medicine, and that he observed the events which he has recorded with the eye of one who practiced the healing art. It is easy to imagine that the presence of a physician might have been of important service to the apostle Paul in his travels; and that his acquaintance with the art of healing may have aided not a little in the furtherance of the gospel. The miraculous power of healing, possessed by the Saviour and his apostles, contributed much to the success of their preaching; for the power of alleviating pain of body - of restoring to health by miracles, would not only be an evidence of the divine origin of their mission - a credential that they were sent from God, but would dispose those who had received such important benefits to listen attentively to the message of salvation. One of the best qualifications in missionaries in modern times, in order to gain access to the pagan, is an acquaintance with the healing art. And Demas - Demas is mentioned in two other places, Phm 1:24, and 2Ti 4:10. He is here spoken of with commendation as one in whom the apostle had confidence. […]