St Thomas Aquinas, Confessor and Doctor
St Thomas, son of the Count of Aquino and of Theodora of Naples, he was at the age of five committed to the care of the Benedictine monks of Monte Cassino.
As a young man he determined, in spite of family opposition, to enter the Order of St. Dominic, whose greatest glory he is. On this occasion he so completely conquered the demon of impurity that from, that time he was exempt from all temptation. His intelligence aided by a supernatural light henceforth sounded the depths of divine mysteries (Introit). Wherefore the Church, comparing him to the spirits of the blessed as much for his innocence as for his genius; awarded him the title of "Angelic Doctor".
"A light of the world" (Gospel), his teaching is such a faithful echo of the "words of true doctrine" of Christ (Epistle), that the Council of Trent placed the Theological Summa next to the Bible in the hall of session. He died in the Cistercian monastery of Fossa Nuova in Campania on his way to the Council of Lyons, March 7th, 1274.
Leo XIII, by letters apostolic, declared him the patron of all Catholic schools. At this season, when the liturgy recalls the public ministry of Jesus, let us ask St. Thomas: so penetrate us with the spirit of penance that we may have a clear vision of the teachings of the Master and put them into practice (Collect), as he did.
In medio Ecclesiae aperuit os ejus: et implevit eum Dominus spiritu sapientiae et intellectus: stolam gloriae induit eum. * Bonum est confiteri Domino: et psallere nomini tuo, Altissime.
In the midst of the Church the Lord opened his mouth: and He filled him with the spirit of wisdom and understanding: He clothed him with a robe of glory. * It is good to give praise to the Lord: and to sing to Thy name, O most High.
(Ecclesiasticus 15:5 and Psalm 91:2 from the Introit of Mass)
Deus, qui Ecclésiam tuam beáti Thomae Confessóris tui mira eruditióne claríficas, et sancta operatióne fecúndas: da nobis, quaesumus; et quae dócuit, intelléctu conspícere, et quae egit, imitatióne complére.
O God, who dost enlighten Thy Church with the wonderful learning of blessed Thomas, Thy confessor, and dost render it fruitful by his holy works, grant us, we beseech Thee, both to understand that which he taught, and to follow his example in what he practised.
From the Catholic Encyclopaedia: http://www.newadvent.org/cathen/14663b.htm