How does the Holy Spirit distribute spiritual gifts?

The Holy Spirit distributes spiritual gifts sovereignly, dividing them to each person individually as He wills, not by human request. The manifestation of the Spirit is given to every man to profit withal, and believers are to be content with the gift God has given.

Les explains that this is a change of operations, but the same God worketh all in all. It is not the believer’s prerogative to ask for a particular gift; rather, the manifestation of the Spirit is given, not asked for. It is given to every man to profit withal. Verse 11 repeats that the selfsame Spirit divides to every man severally, or differently, as He, the Holy Spirit, wills. So the distribution is by His sovereign will, not human selection, and the believer is to be content with the gift God has given.

1 Corinthians 12:11

But all these worketh that one and the selfsame Spirit, dividing to every man severally as he will.

Who decides which spiritual gift each believer receives?

The Holy Spirit decides which spiritual gift each believer receives. Scripture says the manifestation of the Spirit is given, not asked for, and the same Spirit divides to every man severally as He wills. Believers should not request a particular gift but accept the gift God has given and be content.