One had been pope for five years, and the other was an antipope for 18 years. They died as friends.
Meet Saints Pontian, Pope, and Hippolytus, Priest.
Saint Pontian became Pope in the year 230. Five years later, during a period of Christian persecution, he was exiled to the mines in Sardinia. Saint Hippolytus was a priest and well-respected theologian. Then 217, he rebelled against the Church. He, too, was exiled in 235 to the Sardinian mines, where he met Pontian.
But Fr. Dan Cambra, MIC, can tell you the rest:
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