1 Corinthians 14:13

There are, it may be, so many kinds of languages in the world, and none of them is without meaning.

If then I don’t know the meaning of the language, I would be to him who speaks a foreigner, and he who speaks would be a foreigner to me.

So also you, since you are zealous for spiritual gifts, seek that you may abound to the building up of the assembly.

For if I pray in another language, my spirit prays, but my understanding is unfruitful.

What should I do? I will pray with the spirit, and I will pray with the understanding also. I will sing with the spirit, and I will sing with the understanding also.

Otherwise, if you bless with the spirit, how will he who fills the place of the unlearned say the “Amen” at your giving of thanks, seeing he doesn’t know what you say?