Bartholomaeus Sibylla — Bartolomeo Sibilla in Italian, Sybilla on some title pages — was a Dominican of Monopoli in Apulia. He studied at Bologna and Ferrara, received his doctorate in theology at Ferrara in 1478, and became prior of the convent of his order at Monopoli. He died in 1493.
His principal work, the Mirror of Unusual Questions, was first printed in the year of his death and went through several editions over the following century. In three decades of ten chapters it gathers the uncommon questions of theology concerning the soul and its last end, the good angels, and the demons, answering them from Scripture, the Fathers, St. Thomas and the schoolmen, the canonists, and the philosophers.
The Mirror is offered here complete, in English for the first time, from the Venice edition of 1587, which the Dominican Cyprianus Guidus of Lucca revised and restored throughout to conformity with the teaching of St. Thomas, together with its dedicatory letter and both of its indexes.