The Refutation of All Heresies, Book 9

Now Callistus brought forward Zephyrinus himself, and induced him publicly to avow the following sentiments: I know that there is one God, Jesus Christ; nor except Him do I know any other that is begotten and amenable to suffering. And on another occasion, when he would make the following statement: The Father did not die, but the Son. Zephyrinus would in this way continue to keep up ceaseless disturbance among the people. And we, (5) becoming aware of his sentiments, did not give place to him, but reproved and withstood him for the truth’s sake