We know that he was in Rome in the time of Zephyrinus, again in Arabia,.
It was Zephyrinus in A.D.
Zahn acutely suggests that it was omitted in the time of Zephyrinus to counteract Monarchian teaching such as the formula: " believe in one God, Jesus Christ."
Difference of opinion as to the absolutely "irremissible" character of mortal sins led to the important controversy associated with the names of Zephyrinus, Tertullian, Calistus, Hippolytus, Cyprian and Novatian, in which the stricter and more montanistic party held that for those who had been guilty of such sins as theft, fraud, denial of the faith, there should be no restoration to church fellowship even in the hour of death.
As a presbyter of the church at Rome under Bishop Zephyrinus (199-217), Hippolytus was distinguished for his learning and eloquence.
It was probably not long before questions of theology and church discipline brought him into direct conflict with Zephyrinus, or at any rate with his successor Calixtus I.
He was excommunicated by Zephyrinus, despite his remarkable claim that all that bishop's predecessors in the see of Rome had held the humanitarian position.