In this lesson, we find that Luke was a Gentile believer who was a physician and companion of Paul. He actually traveled with Paul all the way to Rome for his imprisonment, and he also wrote the New Testament book of Acts. He wrote both books to Theophilus, who was probably a Roman official, because he is addressed as "Most Excellent." In this 3rd gospel, or good news about Jesus, we find that Luke wrote it so that Theophilus would know the certainty of the things of Jesus, which he had been instructed. As one of my study Bibles said, "Luke's treatises were designed to make him an intelligent believer." The book is also written so that all its readers will become intelligent believers in the Lord Jesus Christ, and that we can KNOW the certainty of Jesus. Luke wrote from eyewitness accounts, in a historical way, so that we get the full story of Jesus, "For the Son of Man has come to seek and to save that which was lost." (19:10)
