Patristic writings on Mary’s purity abound. The Fathers call Mary the tabernacle exempt from defilement and corruption (Hippolytus, “Ontt. in illud, Dominus pascit me”); Origen calls her worthy of God, immaculate of the immaculate, most complete sanctity, perfect justice, neither deceived by the persuasion of the serpent, nor infected with his poisonous breathings (“ Hom. i in diversa”); Ambrose says she is incorrupt, a virgin immune through grace from every stain of sin (“ Sermo xxii in Ps. cxviii); Maximum of Turin calls her a dwelling fit for Christ, not because of her habit of body, but because of original grace (“ Nom. viii de Natali Domini”); Theodotus of Ancyra terms her a virgin innocent, without spot, void of culpability, holy in body and in soul, a lily springing among thorns, untaught the ills of Eve nor was there any communion in her of light with darkness, and, when not yet born, she was consecrated to God (“ Orat. in S. Dei Genitr.”). In refuting Pelagius St. Augustine declares that all the just have truly known of sin “except the Holy Virgin Mary, of whom, for the honour of the Lord, I will have no question whatever where sin is concerned” (De naturâ et gratiâ 36). Mary was pledged to Christ (Peter Chrysologus, “Sermo cxl de Annunt. B.M.V.”); it is evident and notorious notorious that she was pure from eternity, exempt from every defect (Typicon S. Sabae); she was formed without any stain (St. Proclus, “Laudatio in S. Dei Gen. ort.,” I, 3); she was created in a condition more sublime and glorious than all other natures (Theodorus of Jerusalem in Mansi, XII, 1140); when the Virgin Mother of God was to be born of Anne, nature did not dare to anticipate the germ of grace, but remained devoid of fruit (John Damascene, “Hom. i in B. V. Nativ.,” ii).
Charles G. Herbermann. The Catholic Encyclopedia: An International Work of Reference on the Constitution, Doctrine, Discipline, and History of the Catholic Church (Kindle Locations 317682-317692). Catholic Way Publishing. Kindle Edition.