Dominic Guzmán’s Order of Preachers, approved in 1216 by Pope Honorius III, had quickly spread, including to England, where they had appeared in Oxford in 1221.

The thirteenth century is to be the classic age of the Order, the witness to its brilliant development and intense activity, manifested especially in the work of teaching.

The Order by preaching is to reach all classes of Christian society; fight heresy, schism, and paganism by word and book; and by its missions to the north of Europe, to Africa, and Asia will pass beyond the frontiers of Christendom.

Its schools will spread throughout the entire Church; its doctors will write monumental works in all branches of knowledge and two among them, Albertus Magnus, and especially Thomas Aquinas, are to establish a school of philosophy and theology which is to rule the ages to come in the life of the Church.