The Lectionary: How the Catholic Mass Readings Are Chosen
At every Mass, the Church reads from Scripture according to a fixed plan — the Lectionary. In this session of The Mass Explained, Dr. Brant Pitre explains how the Second Vatican Council opened up "the treasures of the Bible… more lavishly" (Sacrosanctum Concilium 51), arranging the Sunday readings in a three-year cycle — Matthew in Year A, Mark in Year B, and Luke in Year C — chosen on three principles: harmony between the Old and New Testament readings (often typology), semi-continuous reading through each Gospel, and the unfolding mysteries of Christ across the liturgical year. He traces the roots of reading Scripture in the assembly to the synagogue, where Jesus stood up to read Isaiah at Nazareth (Luke 4) and where "the Law and the Prophets" were read (Acts 13), and contrasts today's Lectionary with the older one-year cycle of the 1570 Missal of Pius V, which had only two readings (Epistle and Gospel). Along the way he draws on Thomas à Kempis's image of the "two tables" of the Church — the table of God's Word and the table of the Eucharist.
Key passages & sources examined: Jesus reading Isaiah in the synagogue (Luke 4:16–21); the Law and the Prophets read in the synagogue (Acts 13:13–15); "attend to the public reading of scripture" (1 Timothy 4:13); Vatican II on opening the treasures of the Bible (Sacrosanctum Concilium 51); the older one-year lectionary of the Missal of Pius V (1570); and Thomas à Kempis on the "two tables" (Imitation of Christ 4.11).
What is the Lectionary? The Church's official book of Scripture readings for Mass, arranged by day and season.
How does the three-year cycle work? Sundays follow Years A, B, and C, drawing chiefly on Matthew, Mark, and Luke (with John at key seasons).
Why are there usually four readings on Sundays? A First Reading (usually Old Testament), a Responsorial Psalm, a Second Reading (a New Testament letter), and the Gospel — the Old and New Testament readings chosen to illuminate one another.
Is reading Scripture at worship biblical? Yes — Jesus read Isaiah in the synagogue (Luke 4), and "the Law and the Prophets" were read in the synagogue assemblies (Acts 13).
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It is amazing how God has subtly planned salvation to be available to all, through all ages, by the fulfillment of Jesus Christ (Matthew 5:17) and His willingness to take on the Cross. From the Bread of the Presence to the Real Presence in the Eucharist. When you see it, how can you unsee it? When you hear it, how can you unhear it? When you finally get it, how can you ever turn away? “Lord, to whom can we go? You have the words of eternal life." (John 6:68).
It is amazing how God has subtly planned salvation to be available to all, through all ages, by the fulfillment of Jesus Christ (Matthew 5:17) and His willingness to take on the Cross. From the Bread of the Presence to the Real Presence in the Eucharist. When you see it, how can you unsee it? When you hear it, how can you unhear it? When you finally get it, how can you ever turn away? “Lord, to whom can we go? You have the words of eternal life." (John 6:68).
