25 In conclusion, the Testament is said to have been given to the flames by certain men in the time of persecution. Now let its lessons be read, from whatever source it has been brought to light. Certainly in the beginning of the promises of the Testator this is found to have been said to Abraham: "In your seed shall all the nations of the earth be blessed;" and this saying is truthfully interpreted by the apostle: "To your seed," he says, "which is Christ." No betrayal on the part of any man has made the promises of God of none effect.
Hold communion with all the nations of the earth, and then you may boast that you have preserved the Testament from the destruction of the flames. But if you will not do so, which party is the rather to be believed to have insisted on the burning of the Testament, save that which will not assent to its teaching when it is brought to light? For how much more certainly, without any sacrilegious rashness, can he be held to have joined the company of traditors who now persecutes with his tongue the Testament which they are said to have persecuted with the flames!
You charge us with the persecution: the true wheat of the Lord answers you, "Either it was done justly, or it was done by the chaff that was among us." What have you to say to this? You object that we have no baptism: the same true wheat of the Lord answers you, that the form of the sacrament even within the Church fails to profit some, as it did no good to Simon Magus when he was baptized, much more it fails to profit those who are without. Yet that baptism remains in them when they depart, is proved from this, that it is not restored to them when they return.
Never, therefore, except by the greatest shamelessness, will you be able to cry out against that wheat, or to call them false prophets clad in sheep's clothing, while inwardly they are ravening wolves; since either they do not know the wicked in the unity of the Catholic Church, or for the sake of unity bear with those whom they know.
Source: Answer to Letters of Petilian, Bishop of Cirta (New Advent)