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Dec 20, 2019

Understanding the Liturgical Calendar

Dr. James Merrick

Why don’t we just read through the Bible at Mass, verse-by-verse, book-by-book, as some Protestant churches do? Or, why isn’t the priest, like the Protestant pastor, free to decide the Scripture readings he will preach on, based on his pastoral sense of what the people need to hear or what would be relevant for addressing current events? Why do Catholics use a lectionary, a pre-determined schedule of readings? Doesn’t this ensure the Church will always be off topic and out-of-step with daily life? While we are on the subject of the Liturgy of the Word, and since we have just entered a new lectionary year with Advent, let’s recover our sense of the majesty of the Lectionary.  

The Tradition of Reading in Worship

We must keep in mind that for most of history, the public reading of Scripture was the only way it could be known by the majority of the population. Today, we so often have the profoundest encounter with Scripture in the classroom, parish Bible study, or during our own private lectio divina. But for so much of history, it was at the Mass that people encountered the sacred page. Obviously how Scripture is read in the context of corporate worship is going to be different from how an individual might read Scripture to improve his or her own knowledge or how a teacher might present Scripture in the context of an academic classroom.

The Catholic Church inherited the practice of using a Lectionary in worship from the Jewish synagogue where readings revolved around the Jewish feasts. The Torah was read serially (or continuously) while relevant Psalms were sung and selections from the prophets helped the Israelites look forward to the Messiah. The early Church continued to read the Scriptures serially, as the many homilies from the early Fathers demonstrate and as Justin Martyr recounts

As the Church’s liturgical calendar developed and the prayerful contemplation of Scripture in monasteries gave the Church a more profound grasp of its integrity, the Lectionary became much more systematic. Far from being a corruption, this development grew out of the apostles’ own practice of reading the Old Testament in light of Christ’s fulfillment, a practice we find in the pages of the New Testament. This practice led to what’s often called “the principle of harmony.” The principle of harmony assumes that behind all the human authors of Scripture, there is a single divine Author who ensures the unity and harmony of Scripture. The principle of harmony tries to align Scriptures that share the same theme, event, or type. It is most commonly found in the juxtaposition of Old Testament promises or types with their New Testament fulfillment. 

Why Do We Read Scripture in Mass?

If we want to understand why the Catholic Church uses a Lectionary, we have to be crystal clear about the role of Scripture in worship. Our first and foundational duty, at all times and in all places, is to worship God. In the Mass this is especially so. God is eternal and “dwells in light unapproachable” (1 Timothy 6:16). The first commandment forbids us from worshipping God according to our own images and sentiments. We can only worship God rightly by adhering to what he has made known. 

In this way, the act of reading Scripture in Mass serves our worship. Through Scripture, we prevent ourselves from being attached to false notions of God and instead set our hearts and minds upon what God has revealed about himself. In fact, honoring Scripture itself is an act of worship, for it is honoring the very words God gave us by which to know his revelation.

The Lectionary and the Liturgical Calendar

Recognizing that the reading of Scripture is not first for the purpose of our education but for the worship of God helps us understand why the Church reads Scripture according to the life of Jesus Christ and not the Bible’s table of contents. Jesus Christ is the eternal Word of and consubstantial with the Father. He is the definitive revelation of God. Moreover, through the Passion and Cross, he offers the Father the most perfect sacrifice and praise. The Church’s worship cannot improve upon the knowledge given and the worship offered by Jesus Christ. All that the Church can do to worship God faithfully is perpetually celebrate, commemorate, and adore the person and work of Jesus Christ.

This is the reason for the liturgical calendar which leads us through the mysteries of Christ’s life. In Advent, we—like the Old Testament prophets and John the Baptist—anticipate the coming of the Messiah. In Christmas, we celebrate his birth. In the Epiphany, we, like the magi and disciples, discover his true identity as Lord and Savior. In Lent, we mark his temptation in the wilderness, call to repentance and conversion, and journey to Jerusalem. Holy Week commemorates his passion. In Easter we celebrate his resurrection. Ascension and Pentecost mark Christ’s Ascension into heaven and the sending of the Holy Spirit, respectively. During so-called “Ordinary Time” we journey with Christ during his earthly ministry and listen to his teachings. 

The Reading of Scripture and Our Salvation

The Second Vatican Council highlighted the fact that through the Mass, the mysteries of Christ’s life are not merely remembered but re-presented. When Christ ascended into heaven, he did not leave earth, but rather filled it through his Church. If he remained on earth, he could only be present at one place and time. But by his Ascension and the sending of his Holy Spirit, he is present in the Church Catholic (in every time and place). He, as our heavenly high priest and king of the universe, repeats his mysteries throughout the history of the Church. As Dr. Scott Hahn points out:

“the events of Christ’s life pass over into the mysteries, where they are continued in the lives of the believers.”

Letter and Spirit, 29

The Mass by the Word and Eucharist is the moment of this translation of Christ’s life into ours. It is the means by which Christ’s mysteries are perpetuated in history, the way in which salvation comes alive today and is made possible for us. Although not present when they occurred, communicants “communicate” or participate in the realities of salvation through the Mass. As the General Introduction to the Lectionary explains, the Church continually repeats the events of Christ’s life so “it will become clear to the faithful that the history of salvation is continued here and now in the representation of Christ’s paschal mystery celebrated through the Eucharist” (General Introduction to the Lectionary, 61). 

The Modern Lectionary

The Second Vatican Council (1962-1965) had a significant impact on the Church’s Lectionary. The Council proposed a series of pastoral rather than dogmatic reforms, one of the most prominent being the promotion of the Bible amongst the faithful. “The treasures of the Bible,” exhorts the Sacred Constitution on the Liturgy, “are to be opened up more lavishly, so that richer fare may be provided for the faithful at the table of God’s word. In this way a more representative portion of the holy scriptures will be read to the people in the course of a prescribed number of years.” (Sacrosanctum Concilium, 51). 

Dr. Scott Hahn describes well the differences between the pre- and post-Vatican II Lectionaries: 

The old lectionary had covered a one-year cycle; the new book covered three years. The old lectionary’s Sunday readings had been chosen almost exclusively from the gospels and epistles; the new lectionary employed most of the content of most of the books of the Bible, both the Old and New Testaments. In the old lectionary, the Sunday gospels had not been selected in any representative or proportionate way.

Letter and Spirit, 3

For those interested in a complete comparison of the pre- and post-Vatican II lectionaries, Matthew Haskell’s Index Lectionum: A Comparative Table of Readings for the Ordinary and Extraordinary Forms of the Roman Rite is a helpful resource.

As the above quotation from Sacrosanctum Concilium indicated, the aim of exposing the faithful to more Scripture was to be implemented by the introduction of a three-year cycle of readings for Sundays. The three-year cycle is distinguished primarily by which of the synoptic Gospels (Matthew, Mark, and Luke) is read during the year. Year A works through the Gospel of Matthew. Year B, the Gospel of Mark is read, as well as some of the Gospel of John since Mark is so short. The Gospel of Luke is read in Year C. The Gospel of John is also reserved for the Easter season as well as a few other occasions throughout the year. 

The Gospel has thematic control over the first reading and the Responsorial Psalm; they are chosen to correspond to the Gospel reading on the basis of the principal of harmony. The Gospel is the fulfillment of the Old Testament and the subject of the New Testament. The Gospel, then, is at the heart of Scripture. 

It is no surprise that the reading from the Gospels has always been the high point of the Liturgy of the Word. The Gospels contain the narration and words of our Lord. Traditionally the Gospel book has been processed from the altar, both to symbolize the coming of God to humanity in the incarnation, but also as an object of the people’s veneration. The Gospel book was accompanied by an acclamation, candles, and incense, all ancient signs suggesting the Lord is in our midst. 

During the major seasons and feasts of the Church’s year, the Sunday readings are chosen based on the theme of the season or feast. This means the principle of harmony is sometimes suspended. For example, the new Lectionary continues the traditional reading of the Acts of the Apostles for the first lesson through Eastertide. 

During the Sundays in Ordinary Time, the Gospel appointed for the year is read more or less continuously. The first reading and Psalm are chosen in harmony with the Gospel reading. The second reading is chosen from the New Testament, principally from St. Paul’s letters, and it is also read semi-continuously. The second reading in Ordinary Time is not intended to coordinate with the Gospel or the first reading, but there are on occasion some felicitous pairings.

Debate Regarding New Lectionary

While most welcome the new Lectionary’s ability to expose the faithful to more Scripture in the Mass, one major area of controversy concerns its decision to avoid “texts that present real difficulties” (General Introduction to the Lectionary, 76). The General Introduction to the Lectionary does not explain what would constitute a difficulty beyond saying that a difficulty could be either a matter of interpretive confusion (perhaps an apparent contradiction) or a matter of “the ability of the faithful to understand the texts” (76). It does, however, discourage “concealing from the faithful [the reality of Scripture]” and “distorting the meaning of the text” by omissions (77). Whether it has succeeded in this aim will surely be a matter of continued debate


The use of a lectionary goes back to the earliest days of the Church. It is designed to help the Church worship God faithfully by adoring the mysteries of Christ’s life. While some may fear that the pre-determined schedule of readings keeps the Church from being able to be spontaneous and relevant to the concerns of a particular congregation or given week, the Lectionary holds the Church to a higher goal. It calls us to worship God because of who he is and what he has done, and not because of how useful or relevant he is to our times or lives. 

The Lectionary allows the life of Christ to set the agenda, rather than the goals of the preacher or the concerns of the times. If the reading of Scripture was at the discretion of the preacher, then the Church’s knowledge of Scripture would go no higher than the preacher’s knowledge. If the preacher has a skewed view of the Scriptures, then the congregation would likely never hear those texts that don’t fit the preacher’s views. If the Church’s reading of Scripture was determined by relevance to the times, then the Church might only ever hear from the moral teachings of Scripture and miss out on the deeper revelations about the reality of heaven and earth and the eternal identity of Jesus Christ. 

The Lectionary, then, forces the Church to defer to the Word of God. It makes Christ’s life the hermeneutic for our own; it calls us to find our lives in the mystery of Christ’s life. It prevents us from from making our own lives the lens through which we see Christ’s life and using Christ as a prop for our own egos. The Lectionary keeps the Church from reading the Word in light of the times and compels her instead to read the times by the light of God’s Word. 

You May Also Like:

Recovering Love for the Liturgy of the Word

What ‘Liturgy’ Really Means

The Parts of the Mass: The Liturgy of the Word

Dr. James R. A. Merrick is lecturer at Franciscan University of Steubenville, reviews editor for Nova et Vetera, and a theology and Latin teacher at St. Joseph’s Catholic Academy in Boalsburg, Pennsylvania. Dr. Merrick is also on the faculty for the Diocese of Altoona-Johnstown’s Lay Ecclesial and Diaconal Formation program. Previously he was scholar-in-residence at the St. Paul Center for Biblical Theology. Before entering the Church with his wife and children, he was an Anglican priest and college theology professor in the United States and in the United Kingdom. Follow Dr. Merrick on Twitter: @JamesRAMerrick.

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  • Dr Merrick, thank you for this piece. It is one of the great resources I have encountered on the net. The insight gained will further broaden my effort and understanding of this church heritage as a Seminary don.

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