And if you come to the books written after the time of Jesus, you will find that those multitudes of believers who hear the parables are, as it were, “without,” and worthy only of exoteric doctrines, while the disciples learn in private the explanation of the parables. For, privately, to His own disciples did Jesus open up all things, esteeming above the multitudes those who desired to know His wisdom. And He promises to those who believe upon Him to send them wise men and scribes, saying, “Behold, I will send unto you wise men and scribes, and some of them they shall kill and crucify.” And Paul also, in the catalogue of “charismata” bestowed by God, placed first “the word of wisdom,” and second, as being inferior to it, “the word of knowledge,” but third, and lower down, “faith.” And because he regarded “the word” as higher than miraculous powers, he for that reason places “workings of miracles” and “gifts of healings” in a lower place than the gifts of the word.
And in the Acts of the Apostles Stephen bears witness to the great learning of Moses, which he had obtained wholly from ancient writings not accessible to the multitude. For he says: “And Moses was learned in all the wisdom of the Egyptians.” And therefore, with respect to his miracles, it was suspected that he wrought them perhaps, not in virtue of his professing to come from God, but by means of his Egyptian knowledge, in which he was well versed. For the king, entertaining such a suspicion, summoned the Egyptian magicians, and wise men, and enchanters, who were found to be of no avail as against the wisdom of Moses, which proved superior to all the wisdom of the Egyptians.
Source: Against Celsus (New Advent)