1 Corinthians 14:9

King James 2000

So likewise you, except you utter by the tongue words easy to be understood, how shall it be known what is spoken? for you shall speak into the air.

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I therefore so run, not with uncertainty; so fight I, not as one that beats the air:

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