Baring-Gould’s sources: Additions to Usuardus and some editions of the Martyrology of Bede. No authentic account of S. Bertulf exists. All known of him is from a life written in 1703, from old materials, but of what authority it is impossible to decide.

S. Bertulf is said to have been an abbot at Renescure, where the church is dedicated to him. He is regarded also as the patron of Harlebeke, near Courtrai. Renescure is a village on the canal between Aire and S. Omer. His body was taken to Ghent, where it was enshrined in an iron coffin, and for many centuries it was believed that on the approach of danger to the city, the dead abbot knocked against the side of his iron shrine. His bones were scattered by the Calvinists in 1578. S. Bertulf is represented in art in monastic habit distributing alms, with an eagle over his head with wings expanded, a legend relating that he was thus protected from rain in a heavy shower.