Synoptic Gospels texts of the three synoptic gospels often agree very closely in wording and order, both in quotations and in narration. Most scholars ascribe this to "documentary dependence", direct or indirect, meaning the close agreements among synoptic gospels are due to one gospel's drawing from the text of another, or from some written source that another gospel also drew from. The synoptic problem hinges on several interrelated points of controversy: Furthermore, some theories try to explain the relation of the synoptic gospels to John; to non-canonical gospels such as Thomas, Peter, and Egerton; to the Didache; and to lost documents such
New Testament are most often part of an established lectionary (i.e., selected texts to be read at church services on specific days), and (together with an Old Testament reading and a Psalm) include a non-gospel reading from the New Testament and culminate with a Gospel reading. No readings from the Book of Revelation, however, are included in the standard lectionary of the Eastern Orthodox churches. Central to the Christian liturgy is the celebration of the Eucharist or "Holy Communion". The Words of Institution that begin this rite are drawn directly from 1 Corinthians 11:23–26. In addition, the communal recitation of the Lord's