Nicene and Post-Nicene Fathers, Vol. V:
A Treatise Against Two Letters of the...: Chapter 16

Chapter 16.—The Pelagians are Refuted by the Case of the Twin Infants Dying, the One After, and the Other Without, the Grace of Baptism.

But that every lurking-place of your darkness p. 399 may be taken away from you, I have proposed to you the case of such twins as were not assisted by the merits of their parents, and both died in the very beginning of infancy, the one baptized, the other without baptism; lest you should say that God foreknew their future works, as you say of Jacob and Esau, in opposition to the apostle. For how did He foreknow that those things should be, which, in those infants who were to die in infancy, He rather foreknew as not to be, since His foreknowledge cannot be deceived? Or what does it profit those who are taken away from this life that wickedness may not change their understanding, nor deceit beguile their soul, if even the sin which has not been done, said, or thought, is thus punished as if it had been committed? Because, if it is most absurd, silly, and senseless, that certain men should have to be condemned for those sins, the guilt of which they could neither derive from their parents, as you say, nor could incur themselves, either by committing them, or even by conceiving of them, there comes back to you that unbaptized twin brother of the baptized one, and silently asks you for what reason he was made to differ from his brother in respect of happiness,—why he was punished with that infelicity, so that, while his brother was adopted into a child of God, he himself should not receive that sacrament which, as you confess, is necessary for every age, if, even as there is not a fortune or a fate, or an acceptance of persons with God, so there is no gift of grace without merits, and no original sin. To this dumb child you absolutely submit your tongue and voice; to this witness who says nothing,—you have nothing at all to say!