A worshipper who attends the Basil liturgy notices first that it is longer, and that the length lives in the prayers the priest offers at the altar. The visible order of the service, the entrances, the litanies, the Cherubic Hymn, the creed, is shared with the ordinary Chrysostom liturgy, so congregational habit carries smoothly across; what changes is the interior text. The anaphora of Basil is one of the summits of Christian prayer, a sweeping recital of the whole economy of salvation from creation through the fall, the law and the prophets to the incarnation, cross, resurrection and second coming, all addressed to the Father in a single sustained act of thanksgiving before the words of institution and the calling down of the Spirit. Its theology is precise in the Cappadocian manner, and phrases of it read like the Trinitarian debates of the fourth century resolved into doxology.
The Byzantine church assigns this liturgy to the days when such weight is wanted: the Sundays of Great Lent, when the church walks toward Pascha; Holy Thursday, the day of the eucharist's institution; Holy Saturday, the great vigil; the eves of Christmas and Theophany; and the first of January, Basil's own feast. On those ten days the longer prayer slows the whole service down, and the slowing is the point: the church's densest seasons are matched with its deepest text.