1-corinthians 14:7

And even things without life - I may, as if he had said, illustrate this farther by referring to a pipe or harp; if these were to utter mere sounds without order, harmony, or melody, though every tone of music might be in the sounds, surely no person could discern a tune in such sounds, nor receive pleasure from such discords: even so is the person who speaks in an unknown tongue, but does not interpret. His speech tends no more to edification than those discordant and unmeaning sounds do to pleasure and delight.

Things without life - Instruments of music.

Whether pipe - This instrument (αὐλὸς aulos) was usually made of reeds, and probably had a resemblance to a flageolet.

Or harp - This instrument (κιθάρα kithara) was a stringed instrument, and was made in the same way as a modern harp. It usually had ten strings, and was struck with the plectrum, or with a key. It was commonly employed in praise.

Except they give a distinction in the sounds - Unless they give a difference in the "tones," such as are indicated in the gamut for music.

How shall it be known ... - That is, there would be no time, no music. Nothing would be indicated by it. It would not be suited to excite the emotions of sorrow or of joy. All music is designed to excite emotions; but if there be no difference in the tones, no emotion would be produced. So it would be in words uttered. Unless there was something that was suited to excite thought or emotion; unless what was spoken was made "intelligible," no matter how important in itself it might be, yet it would be useless.

14:7 How shall it be known what is piped or harped - What music can be made, or what end answered?