Question: Why Does the Church Have Different Liturgical Cycles?
Answer: While most Catholics know that the Church Year is divided into various seasons (e.g. Advent, Christmas, Ordinary Time, etc.), many are unaware that the one Church Year is not like the one that follows. While the main seasons and feasts are the same from year to year, the 3-year cycle for Sundays and the 2-year cycle for weekdays means that, as a general rule, the readings in the Lectionary that we hear at Mass will change from year to year, helping us to have a richer encounter with Sacred Scripture. Each new cycle begins with the beginning of the liturgical year, the First Sunday of Advent.
The reasoning behind this innovation is outlined in Sacrosanctum Concilium, the “Dogmatic Constitution on the Sacred Liturgy” of the Second Vatican Council: “The treasures of the bible 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” (no. 51). This was fully achieved in 1969 when the new cycles of readings were approved by Pope Saint Paul VI.