Calendars were a necessary component of books which gave the prayers and scriptural readings for church services. Using the calendar, a priest or trained worshipper could determine, for example, what on what date Easter would fall, and which days in a year were Sundays. Also, the calendar lists, month-by-month, other church feasts and saints' days, all of which would have special readings and prayers, which would be assembled the book (missal or breviary). This service book is a rare survival from two English parish churches dating before the Reformation. It was at Ravensworth and Brompton on Swale in Yorkshire. This page presents the prayers that were said by monks early in the morning (matins). The points at which a scriptural text would have to be inserted is indicated in red. For example, at 'Psalmus' a psalm for the day would be sung, as determined using the calendar. These prayers usually appear in a type of service book called a 'breviary' which was used in monasteries. This book provided the prayers for a monk or clergyman outside a monastery. It has some musical notations at some points in it, another indication that it was a compact version of the several books (bibles, hymnals, breviaries) used in monasteries for their daily prayer services.