St. Optatus of Milevis

St. Optatus of Milevis was bishop of Milevis in the Roman province of Numidia in North Africa in the later fourth century, and one of the foremost defenders of Catholic unity against the Donatist schism that then tore the African Church. The Donatists, holding that the sacraments administered by unworthy ministers were invalid and that the true Church was only their own pure remnant, had divided Christian Africa for generations.

Against them Optatus wrote his great work, in seven books, Against the Donatist Parmenian, in which he defended the catholicity and unity of the Church spread throughout the world, argued that the validity of the sacraments depends on Christ and not on the holiness of the minister, and upheld communion with the see of Rome as a mark of the true Church. His work, praised by St. Augustine, who took up and developed the same arguments in his own struggle with the Donatists, is an important witness to early African Christianity. He died about 387, and is venerated as a saint, his memory kept on 4 June.