John Calvin Commentary 1 Corinthians 12:7

"But to each one is given the manifestation of the Spirit to profit withal." — 1 Corinthians 12:7 (ASV)

But the manifestation of the Spirit is given to every man. He now points out the purpose for which God has appointed his gifts, for he does not confer them upon us in vain, nor does he intend that they should serve the purpose of ostentation. Therefore, we must inquire about the purpose for which they are conferred. To this, Paul answers that it is for utility (πρὸς τὸ συμφέρον); that is, so that the Church may receive advantage from them.

The manifestation of the Spirit may be taken in a passive as well as in an active sense: in a passive sense, because wherever there is prophecy, knowledge, or any other gift, the Spirit of God manifests himself there; and in an active sense, because the Spirit of God, when he enriches us with any gift, unlocks his treasures to manifest to us those things that would otherwise have been concealed and hidden. The second interpretation suits better. The view taken by Chrysostom is rather harsh and forced—that this term is used because unbelievers do not recognize God except by visible miracles.