1 Corinthians 14:9

American King James Version (1999)

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

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