The great outlines and all the important events of his life are known, but biographers differ as to some details and dates. Death prevented Henry Denifle from executing his project of writing a critical life of the saint. Denifle's friend and pupil, Dominic Prümmer, O.P., professor of theology in the University of Fribourg, Switzerland, took up the work and published the "Fontes Vitae S. Thomae Aquinatis, notis historicis et criticis illustrati"; and the first fascicle (Toulouse, 1911) has appeared, giving the life of St. Thomas by Peter Calo (1300) now published for the first time. From Tolomeo of Lucca . . . we learn that at the time of the saint's death there was a doubt about his exact age (Prümmer, op. cit., 45). The end of 1225 is usually assigned as the time of his birth. Father Prümmer, on the authority of Calo, thinks 1227 is the more probable date (op. cit., 28). All agree that he died in 1274.Landulph, his father, was Count of Aquino; Theodora, his mother, Countess of Teano. His family was related to the Emperors Henry VI and Frederick II, and to the Kings of Aragon, Castile, and France. Calo relates that a holy hermit foretold his career, saying to Theodora before his birth: "He will enter the Order of Friars Preachers, and so great will be his learning and sanctity that in his day no one will be found to equal him" (Prümmer, op. cit., 18). At the age of five, according to the custom of the times, he was sent to receive his first training from the Benedictine monks of Monte Cassino. Diligent in study, he was thus early noted as being meditative and devoted to prayer, and his preceptor was surprised at hearing the child ask frequently: "What is God?"
About the year 1236 he was sent to the University of Naples. Calo says that the change was made at the instance of the Abbot of Monte Cassino, who wrote to Thomas's father that a boy of such talents should not be left in obscurity (Prümmcr, op. cit., 20). At Naples his preceptors were Pietro Martini and Petrus Hibernus. The chronicler says that he soon surpassed Martini at grammar, and he was then given over to Peter of Ireland, who trained him in logic and the natural sciences. The customs of the times divided the liberal arts into two courses: the Trivium, embracing grammar, logic, and rhetoric; the Quadrivium, comprising music, mathematics, geometry, and astronomy . . . . Thomas could repeat the lessons with more depth and lucidity than his masters displayed. The youth's heart had remained pure amidst the corruption with which he was surrounded, and he resolved to embrace the religious life.
Some time between 1240 and August, 1243, he received the habit of the Order of St. Dominic, being attracted and directed by John of St. Julian, a noted preacher of the convent of Naples. The city wondered that such a noble young man should don the garb of poor friar. His mother, with mingled feelings of joy and sorrow, hastened to Naples to see her son. The Dominicans, fearing she would take him away, sent him to Rome, his ultimate destination being Paris or Cologne. At the instance of Theodora, Thomas's brothers, who were soldiers under the Emperor Frederick, captured the novice near the town of Aquapendente and confined him in the fortress of San Giovanni at Rocca Secca. Here he was detained nearly two years, his parents, brothers, and sisters endeavouring by various means to destroy his vocation. The brothers even laid snares for his virtue, but the pure-minded novice drove the temptress from his room with a brand which he snatched from the fire. Towards the end of his life, St. Thomas confided to his faithful friend and companion, Reginald of Piperno, the secret of a remarkable favour received at this time. When the temptress had been driven from his chamber, he knelt and most earnestly implored God to grant him integrity of mind and body. He fell into a gentle sleep, and, as he slept, two angels appeared to assure him that his prayer had been heard. They then girded him about with a white girdle, saying: "We gird thee with the girdle of perpetual virginity." And from that day forward he never experienced the slightest motions of concupiscence.
The time spent in captivity was not lost. His mother relented somewhat, after the first burst of anger and grief; the Dominicans were allowed to provide him with new habits, and through the kind offices of his sister he procured some books — the Holy Scriptures, Aristotle's Metaphysics, and the "Sentences" of Peter Lombard. After eighteen months or two years spent in prison, either because his mother saw that the hermit's prophecy would eventually be fulfilled or because his brothers feared the threats of Innocent IV and Frederick II, he was set at liberty, being lowered in a basket into the arms of the Dominicans, who were delighted to find that during his captivity "he had made as much progress as if he had been in a studium generale" (Calo, op. cit., 24).
Thomas immediately pronounced his vows, and his superiors sent him to Rome. Innocent IV examined closely into his motives in joining the Friars Preachers, dismissed him with a blessing, and forbade any further interference with his vocation. John the Teutonic, fourth master general of the order, took the young student to Paris and, according to the majority of the saint's biographers, to Cologne, where he arrived in 1244 or 1245, and was placed under Albertus Magnus, the most renowned professor of the order. In the schools Thomas's humility and taciturnity were misinterpreted as signs of dullness, but when Albert had heard his brilliant defence of a difficult thesis, he exclaimed: "We call this young man a dumb ox, but his bellowing in doctrine will one day resound throughout the world."
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