The Gospel of Luke as well as Acts are both authored by Luke. What do we know of him? He was a physician, a travel companion of the Apostle Paul (Colossians 4:14), and something of a historian. The opening verses of the Gospel make it clear that he attempted to research all the facts in a careful manner. It seems that Luke was a Gentile (he was differentiated by the Apostle Paul for the Jews), and Luke clearly writes to a Gentile audience. He goes to special lengths to explain Jewish customs and geography to make it more understandable to his Gentile readers.
As to the theme of this book, it is good to consider his audience. Gentile philosophical thought glorified the human body, and focused on physical reality. Luke presents Jesus as the Perfect Man. Luke’s genealogy traces Jesus’ lineage all the way to Adam, the first man. Jesus’ boyhood mental and physical development are stressed (only) in Luke 2:40-52. In Matthew, we see Jesus as the Son of David, Israel’s King. In Mark, we see Him as the Lord’s Servant, serving others. But in Luke, we see Him as the Son of Man, meeting men’s needs, a perfect man among men. The humanity of Jesus and especially his compassion, are emphasized in Luke’s Gospel. Chapter 15 stands out, with three consecutive stories which tell us not only of the love that Jesus had for sinners and those in need, but also revealing the heart of our Heavenly Father, particularly in the story of the Prodigal Son. The following outline focuses on Jesus as the Son of Man:
I. The Prologue: the Method and Purpose of Writing (1:1-4)
II. The Identification of the Son of Man with Men (1:5-4:13)
III. The Ministry of the Son of Man to Men (4:14-9:50)
IV. The Rejection of the Son of Man by Men (9:51-19:44)
V. The Suffering of the Son of Man for Men (19:45-23:56)
VI. The Authentication (by resurrection) of the Son of Man before Men (24:1-53)