Liturgy 101 - Parts of the Mass #9

For the Sunday Mass, the Responsorial Psalm is followed by the second reading, usually from one of the epistles, which were letters written to the early church.

While the first reading, usually from the Old Testament, reflects the theme of the Gospel, the second reading usually stands alone in regard to theme. This is because the reading is semi-continuous; each Sunday, the reading picks up close to where it left off the previous Sunday, though some passages are not read.

Sunday readings follow a three year cycle, labeled A, B, and C. Weekday readings follow a two year cycle, labeled Year I and Year II. There is one reading on weekdays in addition to the Gospel. It may be taken from the Old or New Testament and, typically, is read semi-continuously (i.e., some passages are not read) until it is finished and a new book is started.