Although no longer included within the Carmelite calendar, the feast of St. Serapion is still listed on October 30th in the 2004 Roman Martyrology.
O God! who hast willed that Blessed Serapion, Thy Confessor and Pontiff, should shine in Thy Church by his learning and virtue; grant, we beseech Thee, that, through the merits and prayers of him whose feast we celebrate, we may imitate his earnestness in the pursuit of true wisdom and holiness. Through our Lord Jesus Christ, Your Son Who lives and reigns with You in the unity of the Holy Spirit one God, forever and ever. Amen.
Serapion is said to have sprung from a noble race. Given to piety from his earliest youth, he was remarkable throughout life for his Christian virtues, and even as a boy he loathed every kind of intemperance. He ever held firmly the Catholic faith; defended it with steadfastness, and longed above all things to shed his blood for it. In his youth be was accomplished in the liberal sciences; but having abandoned the elegant studies of the schools for the pursuit of sacred knowledge, his progress therein was such that he far surpassed the men of his time, and was honored by all as a most wise man. Moved by a divine inspiration, he chose to renounce the world, and to retire to the solitude of Carmel, that he might serve God with greater freedom, and that, aided by the training of monastic life, he might mount to the summit of perfection with a firmer step.
In this training-school the young athlete busied himself with the practice of every virtue; in silence, temperance, and fasting, he was a shining example to his fellows. None were more chaste, none more watchful than he. He prayed much and with such fervor that he seemed sometimes to be rapt in ecstasy. Strengthened by this heavenly exercise, he girded himself to do battle with idolaters and heretics, particularly with them that attacked the Divinity and the reality of the Humanity of Christ, the Lord. The fame of his learning and holiness went forth at length from the retirement of Carmel; and upon the death of Maximinus, Patriarch of Antioch, Serapion was raised to his seat by general consent, and thereby became the eighth Bishop of the church of Antioch, after Saint Peter. In his high position he looked upon his office, not as having been intrusted to him for his own glory, but as demanding greater labor and watchfulness. Therefore he made himself a true model to his flock, taking the utmost care of his sheep, which he nourished with his wisdom and taught by his example.
The Church of God was disturbed at this time by different errors and heresies. Serapion wrote several letters, learned and forcible in style, by which he kept the Christians in the purity of the faith, and in which he attacked the heretics. Many of the latter he brought back to the bosom of Holy Mother Church. He refuted, by his celebrated Commentaries, the Montanists, the Cataphrygians, and the Docetists, of whom the latter (i. e., the Docetists) taught that Christ had no true and real body, but only a phantom body, while the former (the Montanists) declared marriage to be unlawful. The Church of Rhosse, one of the suffragan sees of his Patriarchal Chair, clung to several false legends and doubtful writings. Seeing her wandering from the true faith, Serapion taught her the way of truth, and pointed out to her the path of true Christianity. His writings were remarkable for learning as well as for piety, and in the days of Saint Athanasius they were praised and approved by the Fathers in the Council of Alexandria. This good man, filled with the Holy Ghost and weighed down with years and good deeds, as well as with the many hardships which he had undergone for the Church, peacefully expired on the thirtieth day of October, in the year two hundred and thirteen of the Christian Era.
Taken from the book “Saints of Carmel” (BOSTON: JOHN CASHMAN & CO., 1896).