When we look upon Saint Luke holding a quill and a book, our first thought is that he must be holding his Gospel. However, we may forget that he also authored the Acts of the Apostles as a second volume. Let us then consider how the stained glass depiction can remind us of both the Gospel of Luke and the Acts of the Apostles.

Luke’s Gospel contains many unique details about the early life of Christ and Our Lady: the Annunciation, the Visitation, the prophecies of Simeon and Anna at the Presentation, the finding of Christ in the Temple, the Benedictus prayer of Zechariah, and the Magnificat prayer of Mary. As the diligent and articulate historian he was, Luke may have interviewed Mary to obtain this information. Thus, it is appropriate that his window is next to Mary in our church.

In the Acts of the Apostles, Luke provides a broad survey of the Church’s growth after the Resurrection from its origins in Judaism to its position of world-wide appeal among the Gentiles. Perhaps the circular decoration on the cover of the book Luke holds is meant to represent this growth of the Church. On feast days of the Apostles, the Church prays Psalm 19 to remember this omnidirectional growth of the true faith, like the sun reaching all peoples: “At one end of the heavens is the rising of the sun; to its furthest end it runs its course. There is nothing concealed from its burning heat.”

A final possibility is that Luke holds the "Q" source document, which is hypothesized by many Biblical scholars to be the common source from which Matthew and Luke take their common material that is not found in the Mark's Gospel.