A Lectionary is a table of readings from Scripture appointed to be read at public worship. The association of particular texts with specific days began in the 4th century. The Lectionary [1969, revised 1981] developed by the Roman Catholic Church after Vatican II provided for a three-year cycle of Sunday readings. This Roman lectionary provided the basis for lectionary in The Book of Common Prayer 1979 as well as those developed by many other denominations.
The Common Lectionary, published in 1983, was an ecumenical project of several American and Canadian denominations, developed out of a concern for the unity of the Church and a desire for a common experience of Scripture. It was intended as a harmonization of the many different denominational approaches to the three-year lectionary. It has been in trial use in the Episcopal Church and among the member denominations since 1983.
The Revised Common Lectionary, published in 1992, takes into account constructive criticism of the Common Lectionary based on the evaluation of its trial use and like the current prayer-book lectionary is a three-year cycle of Sunday Eucharistic readings in which Matthew, Mark and Luke are read in successive years with some material from John read in each year.
See “The Revised Common Lectionary” The Episcopal Church: The Episcopal Church and the Revised Common Lectionary.