1 Corinthians 14:2-11

²For the one who speaks in a tongue does not speak to people, but to God; for no one understands, but in his spirit he speaks mysteries. ³But the one who prophesies speaks to people for edification, exhortation, and consolation. ⁴The one who speaks in a tongue edifies himself; but the one who prophesies edifies the church. ⁵Now I wish that you all spoke in tongues, but rather that you would prophesy; and greater is the one who prophesies than the one who speaks in tongues, unless he interprets, so that the church may receive edification.

⁶But now, brothers and sisters, if I come to you speaking in tongues, how will I benefit you unless I speak to you either by way of revelation, or of knowledge, or of prophecy, or of teaching? ⁷Yet even lifeless instruments, whether flute or harp, in producing a sound, if they do not produce a distinction in the tones, how will it be known what is played on the flute or on the harp? ⁸For if the trumpet produces an indistinct sound, who will prepare himself for battle? ⁹So you too, unless you produce intelligible speech by the tongue, how will it be known what is spoken? For you will just be talking to the air. ¹⁰There are, perhaps, a great many kinds of languages in the world, and none is incapable of meaning. ¹¹So if I do not know the meaning of the language, I will be unintelligible to the one who speaks, and the one who speaks will be unintelligible to me.