St. Isidore, Bishop, Confessor, and Doctor
St. Isidore, brother of St. Leander, succeeded him in 601 as Archbishop of Seville (Communion). In his homily on the Gospel of the day, where Jesus compares the apostles and their successors "to the salt of the earth and to the light that sheds its rays on all those within the house," the Saint lays down the duties of a bishop. "Above all a bishop, to accomplish his office must read the Scriptures, study the canons, imitate the examples of the saints, devote himself to watching, fasting and prayer, unite humility with authority and place his chastity under the guard of charity, a virtue without which all the others are nothing."
He realized this ideal. Versed in all knowledge, he was considered the most learned man of his century. An indefatigable preacher of the Gospel, he opposed the Arians and other heretics "who closed their ears to truth and opened them to fables" (Epistle).
Wherefore, hardly 16 years after his death in 636, the Synod of Toledo, composed of 52 Bishops, proclaimed him "excellent Doctor (Collect) and the most recent glory of the Catholic Church".
St. Isidore was for us here below a Doctor of life: may he now intercede for us in heaven (Collect).
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)
O God, who didst give unto Thy people blessed Isidore to be a minister of eternal salvation: grant, we beseech Thee, that we may be worthy to have as an intercessor in heaven him, whom we have had as teacher of life on earth.
From the Catholic Encyclopaedia: http://www.newadvent.org/cathen/08186a.htm