The beginning of a saint's life seems an appropriate place to open this introduction. The Vie de Saint Alexis is of one of the oldest and best-known saints' lives in the French Vernacular and the illuminations prefacing it in the St Albans Psalter are a unique series of images depicting the saint's departure from his home on his wedding night and embarkation on a career of service to God. On the far left, in a room filled by the marriage bed he will leave empty, the saint hands his newly-wed wife his sword-belt and ring. In the centre, the pensive young woman gazes after her departing husband as he steps over the threshold, now partially divided from him by a decorative frame that anticipates their more permanent separation. On the far right, now liberated from the confines of the domestic setting he has left, Alexis pays his fare on the boat that will transport him to a new life devoted to God in Edessa, lifting his eyes towards the heavenly hand that blesses him as he does so. This image sequence neatly encapsulates the focus of this study and the questions it will address. The illuminations – though unusual in iconographical terms – condense many of the themes that I argue are essential to the way saints' lives are composed: notably, renunciation as a form of gift to God and the transformation of social and sexual relationships.