John Chrysostom, on 1Cor 12:7

"But to each one is given the manifestation of the Spirit to profit withal."

Now after this, he comforts him also in another kind of way; by the consideration that the measure vouchsafed is profitable to him, even though it be not so large. For having said, that it is "the same Spirit," and "the same Lord," and "the same God," and having thereby recovered him, he brings in again another consolation, thus saying, "but to each one is given the manifestation of the Spirit to profit withal." For lest one should say, "what if there be the same Lord, the same Spirit, the same God? yet I have received less:" he saith, that thus it was profitable.

But he calls miracles a "manifestation of the Spirit," with evident reason. For to me who am a believer, he that hath the Spirit is manifest from his having been baptized: but to the unbeliever this will in no wise be manifest, except from the miracles: so that hence also again there is no small consolation. For though there be a difference of gifts, yet the evidence is one: since whether thou hast much or little, thou art equally manifest. So that if thou desirest to show this, that thou hast the Spirit, thou hast a sufficient demonstration.

Wherefore, now that both the Giver is one and the thing given a pure favor, and the manifestation takes place thereby, and this is more profitable for thee; grieve not as if despised. For not to dishonor thee hath God done it, nor to declare thee inferior to another, but to spare thee and with a view to thy welfare. To receive more than one has ability to bear, this rather is unprofitable, and injurious, and a fit cause of dejection.