John Chrysostom

"Even things without life, giving a voice, whether pipe or harp, if they give not a distinction in the sounds, how shall it be known what is piped?" "And why do I say," saith he, "that in our case this is unprofitable, and that only useful which is dear and easy to be apprehended by the hearers? Since even in musical instruments without life one may see this: for whether it be pipe or harp, yet if it be struck or blown confusedly and unskilfully, without proper cadence or harmony, it will captivate none of the hearers. …

Homily on 1 Corinthians 35 ↗

Theophylact of Ohrid

And what, he says, am I saying — that what is unclear among us is useless, while what is clear is useful? If even with inanimate instruments the sounds do not "produce distinct tones," that is, clear ones, but everything is mixed together, then it is impossible either to recognize what is being played or to receive pleasure and joy.

Commentary on 1 Corinthians ↗

Thomas Aquinas

Here he shows the same thing with examples taken from inanimate things, namely, instruments which seem to have a voice: first, with instruments of joy; secondly, the instruments of battle (v. 8). He says, therefore: that speaking in tongues does not benefit others is shown not only from what has been said above but also by lifeless things which seem to have a sound. Against this, a voice is a sound uttered from the mouth of an animal. Therefore, lifeless things do not give forth a voice. …

Commentary on 1 Corinthians ↗