13 But let us briefly run through the other matters also, which were spoken of by you abundantly and most fully, especially as Rogatianus, our well-beloved deacon, is hurrying to you. For it follows that they must be asked by us, when they defend heretics, whether their baptism is carnal or spiritual. For if it is carnal, they differ in no respect from the baptism of the Jews, which they use in such a manner that in it, as if in a common and vulgar laver, only external filth is washed away. But if it is spiritual, how can baptism be spiritual among those among whom there is no Holy Spirit? And thus the water wherewith they are washed is to them only a carnal washing, not a sacrament of baptism.
Source: The Epistles of Cyprian (New Advent)