Because Sunday is "the first holy day of all" and the foundation
and core of the whole liturgical year" (Constitution on the Liturgy,
#106), the most important passages of Scripture are presented in the Sunday
lectionary. The weekday lectionary complements the Sunday lectionary.
The Sunday lectionary (book of readings) uses a three-year cycle based on the
three synoptic Gospels (Matthew, Mark and Luke present a "similar view," syn-opsis
in Greek). Each year we concentrate on one of these Gospels: Matthew in Cycle
A, Mark Cycle B, Luke in Cycle C. John's Gospel is featured primarily during
the major seasons or to highlight key doctrines such as the Eucharist.
In addition to a Gospel reading, each Sunday Eucharist has two other readings.
The first reading is usually taken from the Old Testament and is selected in
the light of the theme of the Gospel to be read on that Sunday. The second reading
is taken from the letters of Paul or one of the other writings of the New Testament.
Like the Gospels, these books are read semi-continuously and are selected so
that over the course of the three-year cycle we have a taste of each of the
books of the New Testament.