The Order of Preachers in the thirteenth century had been been the witness to the brilliant development and intense activity of the period.

This last is manifested especially in the work of teaching.

By preaching it had reached all classes of Christian society, fought heresy, schism, and paganism by word and book, and by its missions to the north of Europe, to Africa, and Asia passed beyond the frontiers of Christendom.

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

Thomas Aquinas’s doctrine, although initially received coolly outside his own order, is prescribed for the Dominicans in 1309, more than thirty years after his death.

An enormous number of its members have held offices in Church and State—as popes, cardinals, bishops, legates, inquisitors, confessors of princes, ambassadors, and paciarii (enforcers of the peace decreed by popes or councils).

The expansion of the Order is not without its problems.

The Order of Preachers, which should have remained a select body, has developed beyond bounds and absorbed some elements ill-fitted to its form of life.