What are the major themes of Luke? Who was Luke and to whom was he addressing and what messages was he sending to the recipient/s
When and where was the book written and hat was the source of his message?
Luke was a Gentile, possibly from a Roman family, and a close companion of the Apostle Paul.  He is thought to have been a physician.  Luke also wrote the book of Acts.
The gospel of Luke was written between A.D. 58 and A.D. 60 and his target audience were Gentiles.  Luke probably wrote his account in Rome, although Achaia, Ephesus and Caesarea have also been suggested.
The major theme is Christ Jesus and Luke gives a detailed account of his public ministry up until his resurrection and ascension.  It’s a life history of the “Great Physician” who had great compassion for the outcasts of society, the weak and the under-privileged, sinners and non-Jews.  Luke emphasises the gospel message Jesus proclaimed, that “the kingdom of God is near you”.
The New International Version Study Bible has this to say about the sources Luke drew upon:

Although Luke acknowledges that many others had written of Jesus’ life (1:1), he does not indicate that he relied on these reports for his own writing.  He used personal investigation and arrangement, based on testimony from “eye-witnesses and servants of the word” (1:2) – including the preaching and oral accounts of the apostles. His language differences from the other gospels and his blocks of distinctive material indicate independent work, though he obviously used some of the same sources.

Here is a brief summary taken from an article which provides more information on Luke’s Gospel:

The Gospel of Luke begins by telling us about Jesus’ parents; the birth of His cousin, John the Baptist; Mary and Joseph’s journey to Bethlehem, where Jesus is born in a manger; and the genealogy of Christ through Mary. Jesus’ public ministry reveals His perfect compassion and forgiveness through the stories of the prodigal son, the rich man and Lazarus, and the Good Samaritan. While many believe in this unprejudiced love that surpasses all human limits, many others—especially the religious leaders—challenge and oppose the claims of Jesus. Christ’s followers are encouraged to count the cost of discipleship, while His enemies seek His death on the cross. Finally, Jesus is betrayed, tried, sentenced and crucified. But the grave cannot hold Him! His Resurrection assures the continuation of His ministry of seeking and saving the lost.  Source: https://www.gotquestions.org/Gospel-of-Luke.html

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