Saint Catherine’s Monastery is the oldest continuously inhabited Christian monastery in the world. The monastery predates the divisions of the Christian world and its origins extend to late antiquity.  It’s library is one of the largest libraries of the oldest manuscripts in the world, second only to the Vatican. In 1844 a researcher discovered the Codex Sinaiticus there, dating from the 4th Century, which was at the time the oldest almost completely preserved manuscript of the Bible to have ever been discovered. 
The monastery has the the oldest known surviving roof truss in the world.”  and its main entrance is still marked by the large wooden door that is now 1,400 years old. It is said to have changed very little since the 6th century. 
The doors of the Narthex were made by the Crusaders in the 11th century. Inscriptions can be found on the roof beans, on the carved doors and on the lintel that record Stephanos of Aila as the architect. 
The complex houses irreplaceable works of art such as mosaics, ancient icons, and the best collection of early liturgical objects, chalices and reliquaries. The oldest icon on an Old Testament theme is also preserved there. The monastery contains many pieces of Crusader art, by far the largest collection in existence.  The monastery is a UNESCO World Heritage site.
In addition to the main chapel there are twelve other chapels within the Monastery. The most important is the Chapel of the Burning Bush. Aetheria, a 4th century pilgrim from Spain, tells us of his visiting this site: “We had to advance deep into the valley for there are many hermit cells and a shrine at the site of the Bush. The Bush is verdant to this day. This is the Bush of which I have spoken earlier, the one from which God in a flame of fire spoke to Moses. The Bush is in a very beautiful garden in front of the Church” 
Although known as “Saint Catherine’s Monastery” it’s true official name is the “Sacred Monastery of the God-Trodden Mount Sinai.” It is located at the foot of Mount Sinai in the southern Sinai Peninsula which in the present day is governed by Egypt.
In the first century (60 AD) Josephus reflects the standard rabbinic belief concerning the location of Mount Sinai  so that we can safely say there existed an early Judaic placement of Mount Sinai at Jebel Musa between 100 BC to 30 AD. (See True Mount Sinai article). Local Bedouins who have long inhabited the area have identified Jebel Musa as Mount Sinai. How long this identification has been adhered by them is lost in antiquity.
Pilgrim monks were already settled there when Empress Saint Helena, around 330 A.D. built a church for humanitarian reasons to protect them against raids from nomads who were murderous thieves. She also chose the site for the church from the identification which had been handed down through generations of Bedouins. In addition she reported the site was confirmed to her in a dream.
To protect the numerous monks, who had settled around the alleged site where the biblical burning bush was identified, Justonan (527- 565) established the presence of of St Catherine’s monastery to replace a church which was built there centuries earlier. The older church of St. Helena was incorporated into it. 
Legend says Saint Catherine’s body was transported miraculously by a band of angels to Katrina and her supposedly uncorrupted body was removed to the monastery where her remains are to this very day. Mohammed, prophet of Islam, also identified Jebel Musa as Mount Sinai and gave his personal pledge of protection to the monastery which is still honored by his followers. When Israel occupied Jebel Musa in 1967 they paved a road to Jebel Musa for pilgrims to travel to the sacred mountain. 
The scantiness of the earth makes permanent graves a problem. Therefore monks buried in the cemetery are later exhumed and their bones placed in the ossuary. The piled bones encourages both monks and visitors to meditate on life, death and on the vanity of human and earthly concerns. One of the oldest skeletons is that of a hermit named Stephanos, a 6th century monk, who lived in a lonely cave for many years at Mount Sinai. He is now dressed in the black vestments of a monk with a white cross on his cap. 
Pilgrims from many and varied Christian faiths have throughout history honored the monastery. People of many Christian denominations continue to honor it. The monastery has lived in peace with people of diverse persuasions including the local Bedouins and pilgrims from afar.
By C. Ward
(Please read my article : The True Biblical Mount Sinai: Jebel Musa )
- Brandie Ratliff, “The monastery of Saint Catherine at Mount Sinai and the Christian communities of the Caliphate.” Sinaiticus. The bulletin of the Saint Catherine Foundation (2008)
- Feilden, Bernard M.. Conservation of historic buildings. 3rd ed. Oxford: Architectural Press, 2003. 51. ISBN 0750658630
- The Encyclopedia of Religious Phenomenon, pg 285,
- Kurt Weitzmann in The Icon, Evans Brothers Ltd, London (1982), pp. 201-207 (trans. of Le Icone, Montadori 1981), ISBN 0-237-45645-1
- Against Apion, 2:2 [2:5]
- Lina Eckenstein, A History of Sinai (London & New York, 1921 [AMS Press, New York, 1980 reprint]) pp. 99 fn. 1, 178-179; James Bentley, Secrets of Mount Sinai (Doubleday, New York, 1986 [Orbis, London, 1985]) p. 58; Edith Deen,Great Women of the Christian Faith (Harper & Row, New York, 1959 [Barbour & Co., Westwood, N.J., reprint]) pp. 7-10
- International Standard Bible Enclylopedia, 1911 Edition: Written by C. R. Conder.
- The History of Redemption By Nancy Mahusay