Ante-Nicene Fathers, Vol VIII:
Pseudo-Clementine Literature.: Chapter XVIII

p. 82 Chapter XVIII.—His Profiting by Peter’s Instruction.

To this I answered:  “I give thanks to God Almighty, because I have been instructed as I wished and desired.  At all events, you may depend upon me so far, that I can never come to doubt of those things which I have learned of you; so that even if you yourself should at any time wish to transfer my faith from the true Prophet, you should not be able, because I have drunk in with all my heart what you have spoken.  And that you may not think that I am promising you a great thing when I say that I cannot be moved away from this faith, it is with me a certainty, that whoever has received this account of the true Prophet, can never afterwards so much as doubt of its truth.  And therefore I am confident with respect to this heaven-taught doctrine, in which all the art of malice is overborne.  For in opposition to this prophecy neither any art can stand, nor the subtleties of sophisms and syllogism; but every one who hears of the true Prophet must of necessity long immediately for the truth itself, nor will he afterwards, under pretext of seeking the truth, endure diverse errors.  Wherefore, O my lord Peter, be not further anxious about me, as if I were one who does not know what he has received, and how great a gift has been conferred on him.  Be assured that you have conferred a favour on one who knows and understands its value:  nor can I be easily deceived on that account, because I seem to have gotten quickly what I long desired; for it may be that one who desires gets quickly, while another does not even slowly attain the things which he desires.”