Who was Luke?

Luke traveled with Paul, and probably as his physician. Which was a lowly occupation back then — not like today.

Who Was Luke? As with the other Gospels, the Third Gospel was written by an anonymous author whose identity has been passed down through early Christian writers who lived in the generations after the apostles. According to tradition, Paul’s traveling companion named Luke wrote a two-part work, Luke–Acts, to a patron named Theophilus near the time of Paul’s death. That traveling companion was a physician (Colossians 4:14), and he seems to have come to believe in the gospel message and come into contact with several eyewitnesses to Jesus’s ministry. 

• Wayment, Thomas A.. The New Testament: A New Translation for Latter-day Saints (Kindle Locations 3903-3908). Kindle Edition.