Luke-Acts is the longest and most complex narrative in the New Testament. It was written by an author of literary skill and rich imagination who had a complex vision of the significance of Jesus Christ and of the mission in which he is the central figure. This complex vision is presented in a unified literary work of two volumes.
-- Robert C. Tannehill, The Narrative Unity of Luke-Acts, A Literary Interpretation, p. 1

With each episode, Luke modifies his style accordingly. The thoughts and cares of Mary he expresses in motherly words: he sets the date of the Baptist's initial activity with solemnity; the failed fishing expedition is couched in trade language. The transfiguration is mysterious; Paul's confrontation with the Jews in Rome, polemical. The apostles' prayer and attitude after the ascension is painted in a hieratic fashion, like an icon. Jesus' encounter with Zacchaeus is vivid, moving, and almost naive.
-- Francois Bovon, Luke, p. 3