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 Prummer, O.P., professor of theology in the University of Fribourg, Switzerland, has taken up the work and is publishing 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 (Prummer, op. cit., 45). The end of 1225 is usually assigned as the time of his birth. Father Prummer, 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" (Prummer, 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 (Prummer, op. cit., 20). At Naples his preceptors were Pietro Martini and Petrus Hibernus. The chronicler says that he soon surpassed Martini a 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 " (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 (on chronology of this period see Prummer, op. cit., p.25). 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, hut his bellowing in doctrine will one day resound throughout the world."
In 1245 Albert was sent to Paris, and Thomas accompanied him as a student. In 1248 both returned to Cologne. Albert had been appointed regent of the new , erected that year by the general chapter of the order, and Thomas was to teach under him as Bachelor. (On the system of graduation in the thirteenth century see PREACHERS, ORDER OF—II, A, 1, d). During his stay in Cologne, probably in 1250, he was raised to the priesthood by Conrad of Hochstaden, archbishop of that city. Throughout his busy life, he frequently preached the Word of God, in Germany, France, and Italy. His sermons were forceful, redolent of piety, full of solid instruction, abounding in apt citations from the Scriptures . In the year 1251 or 1252 the master general of the order, by the advice of Albertus Magnus and Hugo a S. Charo (Hugh of St. Cher), sent Thomas to fill the office of Bachelor (sub-regent) in the Dominican at Paris. This appointment may be regarded as the beginning of his public career, for his teaching soon attracted the attention both of the professors and of the students. His duties consisted principally in explaining the "Sentences" of Peter Lombard, and his commentmies on that text-book of theology furnished the materials and, in great part, the plan for his chief work, the "Summa theologica".
In due time he was ordered to prepare himself to obtain the degree of Doctor in Theology from the University of Paris, but the conferring of the degree was postponed, owing to a dispute between the university and the friars. The conflict, originally a dispute between the university and the civic authorities, arose from the slaying of one of the students and the wounding of three others by the city guard. The university, jealous of its autonomy, demanded satisfaction, which was refused. The doctors closed their schools, solemnly swore that they would not reopen them until their demands were granted, and decreed that in future no one should be admitted to the degree of Doctor unless he would take an oath to follow the same line of conduct under similar circumstances. The Dominicans and Franciscans, who had continued to teach in their schools, refused to take the prescribed oath, and from this there arose a bitter conflict which was at its height when St. Thomas and St. Bonaventure were ready to be presented for their degrees. William of St. Amour extended the dispute beyond the original question, violently attacked the Friars, of whom he was evidently jealous, and denied their right to occupy chairs in the university. Against his book, "De periculis novissimorum temporum" (The Perils of the Last Times), St. Thomas wrote a treatise "Contra impugnantes religionem", an apology for the religious orders (Touron, op. cit., II, cc. vii sqq.). The book of William of St. Amour was condemned by Alexander IV at Anagni, 5 October, 1256, and the pope gave orders that the mendicant friars should be admitted to the doctorate.
About this time St. Thomas also combated a dangerous book, "The Eternal Gospel" (Touron, op. cit., II, cxii). The university authorities did not obey immediately; the influence of St. Louis IX and eleven papal Briefs were required before peace was firmly established, and St. Thomas was admitted to the degree of Doctor in Theology. The date of his promotion, as given by many biographers, was 23 October, 1257. His theme was "The Majesty of Christ". His text, "Thou waterest the hills from thy upper rooms: the earth shall be filled with the fruit of thy works" (Ps. ciii, 13), said to have been suggested by a heavenly visitor, seems to have been prophetic of his career. A tradition says that St. Bonaventure and St. Thomas received the doctorate on the same day, and that there was a contest of humility between the two friends as to which should be promoted first. From this time St. Thomas's life may be summed up in a few words: praying, preaching, teaching, writing, journeying. Men were more anxious to hear him than they had been to bear Albert, whom St. Thomas surpassed in accuracy, lucidity, brevity, and power of exposition, if not in universality of knowledge. Paris claimed him as her own; the popes wished to have him near them; the of the order were eager to enjoy the benefit of his teaching; hence we find him successively at Anagni, Rome, Bologna, Orvieto, Viterbo, Perugia, in Paris again, and finally in Naples, always teaching and writing, living on earth with one passion, an ardent zeal for the explanation and defence of Christian truth. So devoted was he to his sacred task that with tears he begged to be excused from accepting the Archbishopric of Naples, to which he was appointed by Clement IV in 1265. Had this appointment been accepted, most probably the "Summa theologica" would not have been written.
Yielding to the requests of his brethren, he on several occasions took part in the deliberations of the general chapters of the order. One of these chapters was held in London in 1263. In another held at Valenciennes (1259) he collaborated with Albertus Magnus and Peter of Tarentasia (afterwards Pope Innocent V) in formulating a system of studies which is substantially preserved to this day in the of the Dominican Order (cf. Douais, op. cit.). It is not surprising to read in the biographies of St. Thomas that he was frequently abstracted and in ecstasy. Towards the end of his life the ecstasies became more frequent. On one occasion, at Naples in 1273, after he had completed his treatise on the Eucharist, three of the brethren saw him lifted in ecstasy, and they heard a voice proceeding from the crucifix on the altar, saying "Thou hast written well of me, Thomas; what reward wilt thou have?". Thomas replied, "None other than Thyself, Lord" (Prummer, op. cit., p. 38). Similar declarations are said to have been made at Orvieto and at Paris. On 6 December, 1273, he laid aside his pen and would write no more. That day he experienced an unusually long ecstasy during Mass; what was revealed to him we can only surmise from his reply to Father Reginald, who urged him to continue his writings: "I can do no more. Such secrets have been revealed to me that all I have written now appears to be of little value" (, Prummer, op. cit., p. 43).
The "Summa theologica" had been completed only as far as the ninetieth question of the third part (De partibus poenitentiae). Thomas began his immediate preparation for death. Gregory X, having convoked a general council, to open at Lyons on 1 May, 1274, invited St. Thomas and St. Bonaventure to take part in the deliberations, commanding the former to bring to the council his treatise "Contra errores Graecorum" (Against the Errors of the Greeks). He tried to obey, setting out on foot in January, 1274, but strength failed him; he fell to the ground near Terracina, whence he was conducted to the Castle of Maienza the home of his niece the Countess Francesca Ceccano. The Cistercian monks of Fossa Nuova pressed him to accept their hospitality, and he was conveyed to their monastery, on entering which he whispered to his companion: "This is my rest for ever and ever: here will I dwell, for I have chosen it" (Ps. cxxxi, 14). When Father Reginald urged him to remain at the castle, the saint replied: "If the Lord wishes to take me away, it is better that I be found in a religious house than in the dwelling of a lay person." The Cistercians were so kind and attentive that Thomas's humility was alarmed. "Whence comes this honour", he exclaimed, "that servants of God should carry wood for my fire!" At the urgent request of the monks he dictated a brief commentary on the Canticle of Canticles.
The end was near; extreme unction was administered. When the Sacred Viaticum was brought into the room he pronounced the following act of faith: "If in this world there be any knowledge of this sacrament stronger than that of faith, I wish now to use it in affirming that I firmly believe and know as certain that Jesus Christ, True God and True Man, Son of God and Son of the Virgin Mary, is in this Sacrament." Then he added: "I receive Thee, the price of my redemption, for Whose love I have watched, studied, and laboured. Thee have I preached; Thee have I taught. Never have I said anything against Thee: if anything was not well said, that is to be attributed to my ignorance. Neither do I wish to be obstinate in my opinions, but if I have written anything erroneous concerning this sacrament or other matters, I submit all to the judgment and correction of the Holy Roman Church, in whose obedience I now pass from this life" (Prummer, op. cit., p. 45). He died on 7 March, 1274. Numerous miracles attested his sanctity, and he was canonized by John XXII, 18 July, 1323. The monks of Fossa Nuova were anxious to keep his sacred remains, but by order of Urban V the body was given to his Dominican brethren, and was solemnly translated to the Dominican church at Toulouse, 28 January, 1369. A magnificent shrine erected in 1628 was destroyed during the French Revolution, and the body was removed to the Church of St. Sernin, where it now reposes in a sarcophagus of gold and silver, which was solemnly blessed by Cardinal Desprez on 24 July, 1878. The chief bone of his left arm is preserved in the cathedral of Naples. The right arm, bestowed on the University of Paris, and originally kept in the St. Thomas's Chapel of the Dominican church, is now preserved in the Dominican Church of S. Maria Sopra Minerva in Rome, whither it was transferred during the French Revolution.
A description of the saint as he appeared in life is given by Calo (Prummer, op. cit., p. 401), who says that his features corresponded with the greatness of his soul. He was of lofty stature and of heavy build, but straight and well proportioned. His complexion was "like the colour of new wheat": his head was large and well shaped, and he was slightly bald. All portraits represent him as noble, meditative, gentle yet strong. St. Pius V proclaimed St. Thomas a Doctor of the Universal Church in the year 1567. In the Encyclical "Aeterni Patris", of 4 August, 1879, on the restoration of Christian philosophy, Leo XIII declared him "the prince and master of all Scholastic doctors". The same illustrious pontiff, by a Brief dated 4 August, 1880, designated him patron of all Catholic universities, academies, colleges, and schools throughout the world.