"If the emperor ask for our letters to Vitalian, answer thus: 'The holy Pope, your Father, has not so enjoined on us; and without his command we can do nothing. But that you may know the straightforwardness of the letters, that they have nothing but entreaties to your piety, to give your mind to the unity of the Church, assign to us some one in whose presence these letters may be read to Vitalian.' But if the emperor require to read them himself, you will answer that you have already intimated not such to be the command of the holy Pope. If he say, 'They may have also other charges,' reply, 'Our conscience forbids. That is not our custom. We come in God's cause. Should we sin against Him? The holy Pope's mission is straightforward; his request and his prayers known to all: that the constitutions of the fathers may not be broken; that heretics be removed from the churches. Beyond that our mission contains nothing.' "If he say, 'For this purpose I have invited the Pope to a council, that if there be any doubt, it may be removed,' answer, 'We thank God, and your piety, that you are so minded, that all may receive what was ordered by the fathers. For then may there be a true and holy unity among the churches of Christ, if, by God's help, you choose to preserve what your predecessors Marcian and Leo maintained.' If he say, 'What mean you by that?' answer, 'That the Council of Chalcedon, and the letters of Pope St. Leo, written against the heretics Nestorius, and Eutyches, and Dioscorus, may be entirely kept'. If he say, 'We received and we hold the Council of Chalcedon, and the letters of Pope Leo,' do you then return thanks, kiss his breast, and say, 'Now we know that God is gracious to you, when you hasten to do this, for that is the Catholic faith which the Apostles preached, without which no one can be orthodox. All bishops must hold to this and preach it.'