To Constantius, Bishop of Milan, on the Faith of Chalcedon

Gregory to Constantius, bishop of Milan. It has come to my knowledge that certain bishops of your diocese, looking for an occasion rather than finding one, have tried to cut themselves off from unity with your fraternity. They say that you gave a written pledge in the city of Rome that you condemned the Three Chapters. In fact they say this because they do not know how I am used to trusting your fraternity even without a pledge. For if anything of the kind had been needed, your word of mouth alone could have been trusted. I, however, do not remember any mention of the Three Chapters between us, either in word or in writing. As for them, if they soon turn back from their error, they should be spared, because, in the words of the apostle Paul, “They understand neither what they are saying nor the things about which they make assertions.” For we, with the truth to guide us and our conscience bearing witness, declare that we keep the faith of the holy Synod of Chalcedon unbroken in every respect, and do not venture to add anything to its definition or to take anything away. But if anyone presumes to think anything, more or less, against it and against the faith of that same synod, we anathematize him without any hesitation and decree him a stranger to the bosom of Mother Church. So anyone whom this confession of mine does not bring to a right mind no longer loves the Synod of Chalcedon, but hates the bosom of Mother Church. If, then, those who seem to have been so daring have presumed to speak this way out of zeal of soul, it remains for them, now that they have received this assurance, to return to unity with your fraternity, and not to divide themselves from the body of Christ, which is the holy universal church. [a]