St-Calais studied under Odo, Bishop of Bayeux, the half-brother of the future William I of England, who was then Duke of Normandy. Other bishops educated at Bayeux around this time included Archbishop Thomas of York and Samson, Bishop of Worcester. Symeon of Durham considered St-Calais to be well-educated in classical literature and the scriptures; at some point St-Calais also acquired a knowledge of canon law. He became a Benedictine monk at Saint-Calais in Maine, where his father had become a monk, and soon became the prior of that house. He became abbot of St Vincent-des-Prés near Le Mans in Maine, sometime around 1078. As abbot, his only appearance in historical records is his upholding of the monasteries' right to some property, and his acceptance of a gift of property in the town.