John Chrysostom, on 1Cor 14:24

But prophecy is not for a sign merely, but is also suitable and useful for faith and for profit unto both classes. And this, if not directly, yet in the sequel he more clearly explained, saying, "he is reproved by all. For, if all prophesy," saith he, "and there come in one unbelieving or unlearned, he is reproved by all; he is judged by all; and thus are the secrets of his heart made manifest; and so he will fall down on his face and worship God, declaring that God is among you indeed."

So that not in this only is prophecy greater, in its availing with each class, but also in its attracting the more shameless of the unbelievers. For it was not the same wonder, when Peter convicted Sapphira, which was a work of prophecy, and when he spake with tongues: but in the former case all shrank into themselves; whereas, when he spake with tongues, he got the credit of being even beside himself.

This then he doth in respect of the tongues, showing that they not only deprive of glory, but also bring shame upon those who have them in the eyes of the unbelievers. But prophecy, on the contrary, is both free from reproach among the unbelievers, and hath very great credit and usefulness. For none will say in regard to prophesying, "they are mad;" nor will any one deride them that prophesy; but, on the contrary, will be astonished at and admire them. For "he is reproved by all," i. e., the things which he hath in his heart, are brought forward and shown unto all: now it is not the same thing for any one to come in and see one speaking in Persian and another in Syriac, and to come in and hear the secrets of his own mind; as whether he cometh in as a tempter and with evil mind, or sincerely; or that such and such a thing hath been done by him, and such another designed. For this is much more awful and more profitable than the other. For this cause therefore, whereas of the tongues he saith, "ye are mad;" not however affirming this of himself, but of their judgment: i. e., "they will say," saith he, "that ye are mad;" here, on the contrary, he makes use both of the verdict of the facts, and that of those who are the objects of the benefit. "For he is reproved by all," saith he, "he is judged by all; and thus are the secrets of his heart made manifest; and so he will fall down on his face and worship God, declaring that God is around you indeed. Seest thou that this is not capable of two interpretations: how in the former case what is done may be doubted of, and here and there an unbeliever might ascribe it to madness? whereas here there will be no such thing, but he will both wonder and worship, first making a confession by his deeds, and then by his words also. Thus also Nebuchadnezzar worshipped God, saying, "Of a truth, your God, He is the God that revealeth secrets, seeing thou couldest reveal this secret." Seest thou the might of prophecy, how it changed that savage one and brought him under instruction and introduced him to faith?