The Christian ascetic way of life clustered mainly around the Mediterranean and roughly covered the period between 350 and 800. It is determined by norm and exercise. But what are norm and exercise with regard to Christian asceticism? Whatever renunciations may be required in order to practice a given ascetic regimen, no goal can be achieved without a specific technique (or a set of exercises) and without following a principle of order (or a norm). This implies an intense dialectic which sometimes seems to resolve into a perfect identity: regula et vita, "rule and life", or, in a more neutral language, "norm and exercise". This set of papers addresses this crucial point and thereby challenges the usual chronological as well as geographical divisions in the history of early Christianity. As a result, the categories of norm and exercise are presented as a new solution to put the available sources in order.