1 Corinthians 14:9-11

Living_Oracles(i) 9 So, also, you, unless with the tongue you give intelligible speech, how shall it be known what is spoken? Therefore, you will be speaking to the air. 10 There are, perhaps, so many kinds of languages in the world, and none of them is without signification. 11 Yet, if I do not know the meaning of the language, I shall be to him who speaks, a foreigner; and he who speaks, will be a foreigner to me.