It is manifest from his Gospel, that Luke was both an acute observer, and had even given professional attention to all our Saviour's miracles of healing. Originally, among the Egyptians, divinity and physic were united in the same order of men, so that the priest had the care of souls, and was also the physician. It was much the same under the Jewish economy. But after physic came to be studied by the Greeks, they separated the two professions. That a physician should write the history of our Saviour's life was appropriate, as there were divers mysterious things to be noticed, concerning which his education enabled him to form a becoming judgment. It is even interesting to realize that St. Luke's tendency to use medical terms has been of definite value in determining the question whether both the third gospel and the Acts of the Apostles are by the same man. They have been attributed to St. Luke traditionally, but in the higher criticism some doubt has been thrown on this and an elaborate hypothesis of dual authorship set up. It has been asserted that it is very improbable on extrinsic grounds that they were both written by one hand and certain intrinsic evidence, changes in the mode of narration, especially the use of the first personal pronoun in the plural in certain passages, has been pointed to as making against single authorship. This tendency to deny old-time traditions of authorship with regard to many classical writings was a marked characteristic of the early part of the nineteenth century, but the close of the century saw practically all of these denials discredited. The nineteenth century ushered in studies of Homer, with the separatist school perfectly confident in their assertion that the Iliad and the Odyssey were not by the same person, and even that the Iliad itself was the work of several hands.