The religious rule that had the greatest impact on the development of monasticism in the Western Church was the Rule of St. Benedict. Its creation is attributed to St. Benedict of Nursia.

St. Benedict created his Rule in the monastery at Monte Cassino in around 540 A.D.
It contains a set of rules and standards for the monks’ cenobitic way of life, as well as ascetic guidelines.
It was created from St. Benedict’s personal experience, but is also based on the Holy Scriptures, works of the Fathers of the Church, and achievements of Eastern and Western monasticism.

The thing which highlights St. Benedict’s Rule among the others of those times is that it is the only universal one. The rest were written for one specific monastery and were often modified by subsequent communities. Benedict of Nursia drew inspiration for his Rule from an older text: the Rule of the Master, which was probably written in the first half of the 6th century. The Benedictine Rule spread gradually in Europe, mainly due to Anglo-Saxon monks. In the 9th century, the Rule was completed by St. Benedict of Aniane, who collected the known Latin rules of the time into two works. At the synod of 813 A.D., with the support of Louis I of the Pious, he managed to introduce the Benedictine rule as binding in all monasteries in what was then the Frankish Empire. From the 8th to the 13th century, the Rule of St. Benedict was the most popular religious rule in Europe until the arrival of the Mendicant Congregations (such as the Dominicans and Franciscans).

A characteristic feature of the rule of St. Benedict is the standard that he orders his apprentices to follow, which is summarized in two famous Benedictine mottos: “Ora et labora” (pray and work) and “Ordo e pax” (law and order). The rule also introduced the division of the day into three parts, with eight hours for each part. The time in the day should be divided evenly between work, prayer and meditation on the Scriptures, and study and rest.

They were also obliged to make three vows: stability, obedience and observance of the Rule, and obedience to the evangelical counsels, which are poverty, chastity and obedience.