Scripture Readings Throughout the Year

The annual cycle of the Gospels is composed of four series:

1. The Gospel of St. John is read from Pascha until Pentecost Sunday
2. The Gospel of St. Matthew readings are divided over seventeen weeks beginning with the Monday of the Holy Spirit (the day after Pentecost). From the twelfth week, it is read on Saturdays and Sundays while the Gospel of St. Mark is read on the remaining weekdays
3. The Gospel of St. Luke divided over nineteen weeks beginning on the Monday after the Elevation of the Holy Cross, interrupting the cycle. From the thirteenth week, it is only read on Saturdays and Sundays, while St. Mark's Gospel is again read on the remaining weekdays
4. The Gospel of St. Mark is also read during the Lenten period on Saturdays and Sundays with the exception of the Sunday of Orthodoxy. 

The annual cycle of Apostolic readings 

• The Acts of the Apostles begin on Pascha and continue through Pentecost.
• Epistle readings start on the Tuesday after Pentecost,  Romans begins and the readings continue pretty much in order with the rest of the New Testament books. The more important readings are generally done on a Sunday or a Saturday with the others on the weekdays.
• The Book of Revelation is not used in the Lectionary cycle, probably because this cycle pre-dates the addition of this book to the Bible.

Nativity interruption and yearly adjustment

From about two Sundays before Christmas to the Sunday after the Theophany advent - Nativity -Theophany readings interupr the cycle.  And after that, and before the Pre-Lenten Season,  there is usually an adjustment to the cycle. Readings may be repeated or skipped depending on when Pascha fell the previous year and when it falls in the coming year. On Zacchaeus Sunday, the Sunday before the Triodion begins, the apostolic reading for the 32nd Sunday after Pentecost, and the gospel reading for the 15th Sunday of Luke, is used. This is where readings may be skipped if needed. If readings need to be repeated, many churches just count backwards from this Sunday back to the Nativity - Theophany interruption. (This skipping or repeating of scripture readings does not change the cycle of Tones (Prokeimenon or Alleluia Verses).

Other readings

There are also prescribed readings for Sunday and Feastday Matins, Fixed Feastday and Lenten vespers, Feastday Liturgies,  and some other occasions such as Weddings, Baptisms, and Burials. 

Because of the Fixed Feasts, a particular day of the liturgical year may have more then one set of readings, those based on the movable cycle listed above, and those based upon the fixed date cycle. In some cases the readings of the movable cycle outrank those of the fixed cycle such as Pascha, and in other cases the fixed cycle outrank those of the movable cycle such as the Nativity.