65 Then who is there that could fail to perceive from what a vein of conceit it proceeds, that in explaining as it were the declaration of the apostle, he says, "He who said, ‘I planted, Apollos watered, but God gave the increase,' surely meant nothing else than this, that ‘I made a man a catechumen in Christ, Apollo baptized him; God confirmed what we had done?'" Why then did not Petilianus add what the apostle added, and I especially took pains to quote, "So then neither is he that plants anything, neither he that waters; but God that gives the increase"? And if he be willing to interpret this on the same principle as what he has set down above, it follows beyond all doubt, that neither is he that baptizes anything but God that gives the increase.
For what matter does it make in reference to the question now before us, in what sense it has been said, "I planted, Apollos watered,"— whether it is really to be taken as equivalent to his saying, "I made a catechumen, Apollos baptized him;" or whether there be any other truer and more congruous understanding of it?— for in the mean time, according to his own interpretation of the words, neither is he that makes the catechumen anything, neither he that baptizes, but God that gives the increase.
But there is a great difference between confirming what another does, and doing anything oneself. For He who gives the increase does not confirm a tree or a vine, but creates it. For by that increase it comes to pass that even a piece of wood planted in the ground produces and establishes a root; by that increase it comes to pass that a seed cast into the earth puts forth a shoot. But why should we make a longer dissertation on this point? It is enough that, according to Petilianus himself neither he that makes a catechumen, nor he that baptizes, is anything, but God that gives the increase.
But when would Petilianus say this, so that we should understand that he meant, Neither is Donatus of Carthage anything, neither Januarius, neither Petilianus? When would the swelling of his pride permit him to say this, which now causes the man to think himself to be something, when he is nothing, deceiving himself?
Source: Answer to Letters of Petilian, Bishop of Cirta (New Advent)