Here is the oration that the Church prays in the Mass and Office for Saint Didacus of Alcalá (November 13):
Omnípotens sempitérne Deus, qui dispositióne mirábili infírma mundi éligis, ut fórtia quæque confúndas: concéde propítius humilitáti nostræ; ut, piis beáti Dídaci Confessóris tui précibus, ad perénnem in cælis glóriam sublimári mereámur.
Here is my translation:
Almighty and eternal God, who, by an astonishing arrangement, hast chosen the weak things of the world, that Thou mayest confound all of the strong: mercifully grant to our lowliness that, by the pious prayers of blessed Didacus Thy Confessor, we may deserve to be raised to everlasting glory in Heaven.
Here is the translation from the Divinum Officium site:
O Almighty and everlasting God, Who in thy wonderful ordinance dost choose the weak things of the world to bring to nought the things that are strong, mercifully grant unto us thine unworthy servants, at the kindly prayers of thy blessed Confessor Diego, worthily to attain unto everlasting glory in heaven.
The Biblical reference is to 1 Cor. 1:27:
But the foolish things of the world hath God chosen, that he may confound the wise; and the weak things of the world hath God chosen, that he may confound the strong. (Sed quae stulta sunt mundi elegit Deus, ut confundat sapientes : et infirma mundi elegit Deus, ut confundat fortia.)
The reference to “weak things,” and lowliness clearly invokes Saint Didacus’ humble status as a lay brother in the Observant branch of the Franciscans (a reform group within the Friars Minor). Though he was “just a brother,” he was, contrary to custom, made the guardian (superior) of one of the Observant houses in the new mission territory where the friars labored in the Canary Islands. Previously he had served as porter, hence the keys shown on his cord in the Zurbarán painting. This makes him one of many canonized porters in the Church. Eventually, he would be known as a miracle worker, healing plague victims at the infirmary attached to the Ara Coeli in Rome. His death was the result of an infectious abscess which, instead of the expected foul odor, emitted a very pleasant scent that continued even after the saint died and his body remained incorrupt.
A common Biblical theme in both Testaments is the exultation of the humble. Our Lady invokes it in the Magnificat: “He hath put down the mighty from their seat, and hath exalted the humble” (Luke 1:52). In this oration for Saint Didacus, we acknowledge that we are “unworthy” or “lowly” as we also ask to be raised to heavenly glory. By the prayers of Saint Didacus, the humble Franciscan Friar, may it be so!
Under the Spanish form of his name, San Diego, Saint Didacus is the eponym of the well known city in California. The Franciscan mission there, founded by Saint Junípero Serra on July 16, 1769, was dedicated to Saint Didacus. Pope Paul VI made it a minor basilica in 1976. As with many of California’s municipalities, the city that later grew around the mission took the name of the mission’s titular patron.