God has made us to be rhythmic creatures and medical science has recognized the circadian rhythm that is programmed into our physiology. Therefore, it is no surprise that cyclic daily devotions are a part of all religions, not just the Judeo-Christian faiths. The Church has always had specific times of the day set aside for devotions since the early days. This is based on the Jewish devotional practices of praying morning, noon and evening prayers. The apostles met together in the Book of Acts to continue to carry out these prayer times at the third sixth and ninth hour. (Acts 10:3, 9, 16:25)
Later on in the life of the Church the monastic communities developed the Liturgy of the Hours and to this day priests and deacons and religious continue to observe the Divine Office of prayer. This usually consists of a reading from Psalms, with a responsorial, a reflection on the feast day of the saint as well as the gospel reading for the day along with specific prayer intentions.
The Angelus prayer pictured above can be traced back to the 14th century. It was prayed three times a day at the ringing of the Church bells reminding the faithful to stop everything for morning, noon and night prayers. Would that we all had some reminder during the day to take a few moments three times daily to turn our hearts towards Christ. I don't view it as legalistic but a beautiful way the Church takes advantage of the circadian nature of His creation.
When I first went into medical practice and was decorating the waiting room of my office, I bought the Angelus painting above at an art store. I loved the simple beauty of devotion this young couple displayed as they paused in the field to pray. It wasn't until years later and after my conversion that I found out the young couple was praying the Angelus devotion and this was an ancient Catholic devotion.
Source: pagan-space.blogspot.com