The Book of Hours, which was developed during the medieval monastic period, specifies different prayers for different times of the day. This can be seen as an attempt to pray without ceasing. The Christian monastic movement was a highly organized experience of keeping a focus on God and away from more mundane concerns.
Taking between five and twenty minutes to meditate at specified times creates a strong framework for the work and play of the day and reflects the concerns of the Book of Hours as well as the practices of the early Christian community.
Walking This Practice into the World
Set reminders or alarms for a few times of day to pause, take a few deep breaths, and remember your connection to God. Call to mind the vast network of faithful people throughout history and around the world and join your prayers to theirs.
— Don Mackenzie in Finding Peace through Spiritual Practice by Don Mackenzie, Ted Falcon, Jamal Rahman