Benedict wrote his rule about AD 530, drawing on the Bible and on earlier rules by Augustine and Basil but mainly on the Rule of the Master. Nevertheless, Benedict’s and the Master’s understandings of the roles of abbot, rule, and community were quite different. Benedict encouraged his monks to read other monastic sources. During the next five hundred years, monks gave varying weight to the authority of the Bible, the Rule, abbots, monastic tradition, and local tradition in deciding how to live the monastic life. The chapter examines developments in the monasteries of Fulda and La Chaise-Dieu as case studies illustrating the different ways in which monks regarded the role of the Rule of Benedict as the norm governing monastic life.