St. Cletus I
Emperor Vespasian reigned in Rome when Cletus assumed leadership of the Church. His specific responsibilities, like those of his predecessor Linus, can only be surmised because a monarchial episcopate had not yet emerged in Rome. Little is known of Cletus, perhaps due to the confusion over his name (q.v. footnote on p. 9 of the Liber Pontificalis for information on the double entry). Some historians refer to him as Anacletus or, more correctly, Anencletus, which is a Greek adjective meaning “blameless.” There is, however, no doubt that he is recognized as the third successor and is commemorated in the ancient canon of the Mass.
Ordained by St. Peter himself, according to tradition he appointed twenty-five presbyters for Rome and erected a shrine over the burial place of Peter. He is said to have died a martyr, in the twelfth year of the reign of Emperor Domitian, and was buried on the Vatican Hill.
St. Marcellinus succeeded St. Caius as Pope during the Diocletian persecution (296-304). With wise forethought he ordered large rooms to be constructed in the catacombs for liturgical use. Such a chamber in the catacomb of Callistus still recalls his action.
According to the Liber Pontificalis, this pope offered incense before pagan gods when arrested during the persecution. Of this, Gueranger wisely notes (and it bears repeating): “We scarcely need to remind the reader that the fall of Marcellinus, supposing it to be a fact, would be no argument against the infallibility of the Roman Pontiff. The Pope cannot teach error when he addresses himself to the Church, but he is not impeccable in his personal conduct.” In any event, he is said later to have atoned for his weakness by a very tearful, public penance and subsequent glorious martyrdom. He was interred in the Priscillian catacomb on the Via Salaria, and his grave was an object of highest honor.