1 Corinthians 14:9 KJV
So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air.
1 Corinthians 14:9, King James Version
In context
8 For if the trumpet give an uncertain sound, who shall prepare himself to the battle?
9 So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air.
10 There are, it may be, so many kinds of voices in the world, and none of them is without signification.