7. Nevertheless, lifeless instruments making a sound, whether flute or harp, if they do not make a distinction in the sound, how shall it be known what is played on the flute or on the harp?
8. For indeed, if the trumpet makes an indistinct sound, who shall prepare himself for battle?
9. So also you, if you do not give speech by the tongue that is clear, how shall it be known what is spoken? For you shall be speaking into the air.
10. There are, undoubtedly, so many kinds of sounds in the world, and none of them is without distinct sound.
11. If then I do not know the power of the voice, I shall be a foreigner to him who speaks, and he who speaks be a foreigner to me.
12. So also you, since you are ardent for spiritual gifts, seek to excel in the upbuilding of the assembly.
13. Therefore, he who is speaking in a tongue, let him pray that he might interpret.
14. For if I am praying in a tongue, my spirit is praying, but my understanding is without fruit.
15. What then is it? I shall pray with the spirit, and I shall also pray with the understanding. I shall sing with the spirit, and I shall also sing with the understanding.
16. Otherwise, if you bless with the spirit, how shall he who fills up the place of the unlearned say “Amĕn” at your giving of thanks, since he does not know what you say?