Prayer has been an essential part of Christianity since its earliest days. As the Middle Ages began, the monastic traditions of both Western and Eastern Christianity moved beyond vocal prayer to Christian meditation. These progressions resulted in two distinct and different meditative practices: Lectio Divina in the West and hesychasm in the East. Hesychasm involves the repetition of the Jesus Prayer, but Lectio Divina uses different Scripture passages at different times and although a passage may be repeated a few times, Lectio Divina is not repetitive in nature. The progression from Bible reading, to meditation, to loving regard for God, was first formally described by Guigo II, a Carthusian monk who died late in the 12th century. Guigo II's book The Ladder of Monks is considered the first description of methodical prayer in the western mystical tradition. In Eastern Christianity, the monastic traditions of "constant prayer" that traced back to the Desert Fathers and Evagrius Pontikos established the practice of hesychasm and influenced John Climacus' book The Ladder of Divine Ascent by the 7th century. These meditative prayers were promoted and supported by Saint Gregory Palamas in the 14th century. From the 18th century some components of meditation began to be de-emphasized in some branches of Western Christianity. However, the early part of the 20th century witnessed a revival and books and articles on approaches such as Lectio divina aimed at the general public began to appear by the middle of the century. In 1965 one of the principal documents of the Second Vatican Council, the dogmatic constitution Dei verbum (Latin for Word of God) emphasized the use of Lectio divina and on the 40th anniversary of Dei verbum in 2005 Pope Benedict XVI reaffirmed its importance.<ref name=spring >[https://www.vatican.va/holy_father/benedict_xvi/speeches/2005/september/documents/hf_ben-xvi_spe_20050916_40-dei-verbum_en.html Vatican website Address at the 40th anniversary of DEI VERBUM, Friday, 16 September 2005]</ref> Early Christianity The history and origins of Christian meditation have been intertwined with that of monastic life, both in the East and the West. By the 4th century, groups of Christians, who came to be called the Desert Fathers, had sought God in the deserts of Palestine and Egypt, and began to become an early model of monastic Christian life.Globalization of Hesychasm and the Jesus Prayer: Contesting Contemplation by Christopher D. L. Johnson 2010 pages 31-38 The tradition of a Christian life of "constant prayer" in a monastic setting began in this period. I In the 5th