Used as a prayerbook as well as a book of hymns for church services, the psalter in the later middle ages was often produced with a calendar and additional prayers. Eventually it was combined with an abridged version of the breviary, the prayerbook used by monks, to form the special lay prayerbook, the book of hours. This psalter represents an important stage in this development as it took place in England. It is one of the earliest psalters to include the Hours of the Virgin, a special set of devotions taken from the breviary. Also it is the earliest of a line of richly decorated psalters which were probably made at Oxford, in the workshops by lay scribes and artists, an industry which grew out of book production for the university. The book originally began with a series of scenes, two to a page, within an elaborate border. These would have been devotional aids to the book's reader, helping them to contemplate the life of Christ. The main events of the gospels are depicted chronologically. The series ends with depictions of Pentecost (the descent of the Holy Spirit upon the apostles and the Virgin) and Christ in Majesty (Christ enthroned in heaven surrounded by the four creatures--believed to symbolise the gospels, the first words of which appear on banners--as described in the Book of Revelations).