It's understandable that users of the Revised Common Lectionary might have these questions. One way to answer them would be to note that the Consultation on Common Texts, the ecumenical committee charged with developing the reading selections, negotiated a variety of perspectives that occasionally called for additional inclusions of texts. Representatives of the many faiths and denominations participating in this ecumenical effort determined that in some cases only adding additional options to a service day's reading would sufficiently represent the perspectives of the participants or the unique theological/historical focus of the day. The Consultation on Common Texts understood that to bring the Revised Common Lectionary to common acceptance across the community of Christian faith, the commonality would need to include some flexibility.

The most significant number of options occurs during the Season after Pentecost. One strand of Old Testament readings follows major stories/themes, read mostly continuously, beginning in Year A with Genesis and ending in Year C with the later prophets. A different strand of readings follow the centuries-old historical tradition of thematically pairing the Old Testament reading with the Gospel reading, often typologically, with the presaging of Jesus Christ's life and ministry. The Consultation on Common Texts designed the Lectionary to make use of either of these strands, but once a strand has been selected, it should be followed through to the end of the Pentecost season. Within each strand there may be additional readings, readings which are complementary to the standard reading; these may be used with the standard reading, or in place of it. These complementary readings are indicated by italics; complementary readings appear throughout the church year, not just during the Season of Pentecost.