52 These things, I think, I put with clearness and truth in my former epistle, when I made answer to Petilianus. These things I have also now quoted, intimating and commending to you the truth that our faith rests on something else altogether than man, and that we believe that the Lord Christ is the cleanser and the justifier of men that believe in Him that justifies the ungodly, that their faith may be counted unto them for righteousness, whether the man who administers the baptism be righteous, or such an impious and deceitful man as the Holy Spirit flees.
Then I went on to point out what absurdity would follow were it otherwise, and I said, as I say now: "Otherwise, if each man is born again in spiritual grace of the same sort as he by whom he is baptized, and if, when he who baptizes him is manifestly a good man, then he himself gives faith, he is himself the origin and root and head of him who is being born; while, when the baptizer is faithless without its being known, then the baptized person receives faith from Christ, then derives his origin from Christ, then he is rooted in Christ then he boasts in Christ as his head; in that case all who are baptized should wish that they might have faithless baptizers, and be ignorant of their faithlessness.
For however good their baptizers might have been, Christ is certainly beyond comparison better still, and He will then be the Head of the baptized if the faithlessness of the baptizer shall escape detection. But if it be perfect madness to hold such a view (for it is Christ always that justifies the ungodly, by changing his ungodliness into Christianity; it is from Christ always that faith is received; Christ is always the origin of the regenerate, and the Head of the Church), what weight then will those words have, which thoughtless readers value by their sound, without inquiring what their inner meaning is?" This much I said at that time; this is written in my epistle.
Source: Answer to Letters of Petilian, Bishop of Cirta (New Advent)