Ecclesiastical life was followed by clerics, priests, monks and nuns. These were living in and working in cathedrals and parish churches, monasteries and other Christian institutions where they endeavored to follow the commandment to pray without ceasing. One of the principle methods for doing so was to observe religious services at regular intervals throughout the day. This became standardized to holding a service every three hours. This cycle of services observed throughout the day became known as Canonical Hours or Offices, or Liturgical Hours.. These services were held, for example, at 6 am, 9 am, 12 noon and so on throughout the day. Monks in a monastery, clerics in a cathedral would leave their work and assemble in the chapel for a short service, often of 15-20 minutes, consisting of prayers, praise and singing, and Bible reading. This tradition developed quite early in Church history, becoming widely recognized in the 3rd century. In early practice, ...