Let us take the noble examples of our own generation. It was due to jealousy and envy that the greatest and most holy pillars were persecuted and fought to the death. Let us pass in review the good Apostles: a Peter, who through unmerited jealousy underwent not one or two, but many hardships and, after thus giving testimony, departed for the place of glory that was his due. Through jealousy and strife Paul demonstrated how to win the prize of patient endurance: seven times he was imprisoned; he was forced to leave and stoned; he preached in the East and the West; and, finally, he won the splendid renown which his faith had earned. He taught the right manner of life to the whole world, traveled as far as the Western boundary, and, when he had given testimony before the authorities, ended his earthly career and was taken up into the holy place as the greatest model of patient endurance.
-- Pope Saint Clement I of Rome from The First Epistle of Clement to the Corinthians