9 So with yourselves, if with your tongue you utter speech that is not intelligible, how will anyone know what is said? For you will be b speaking into the air. 10 There are doubtless many different languages in the world, and none is without meaning, 11 but if I do not know the meaning of the language, I will be c a foreigner to the speaker and the speaker a foreigner to me. 12 So with yourselves, since you are eager for manifestations of the Spirit, strive to excel in building up the church.