131. Whence also the Son of God said concerning the Holy Spirit: “He shall not speak from Himself,” that is, not without the participation of the Father and Myself. For the Spirit is not divided and separated, but speaks what He hears. He hears, that is to say, by unity of substance and by the property of knowledge. For He receives not hearing by any orifices of the body, nor does the divine voice resound with any carnal measures, nor does He hear what He knows not; since commonly in human matters hearing produces knowledge, and yet not even in men themselves is there always bodily speech or fleshly hearing. For “he that speaketh in tongues,” it is said, “speaketh not to men but to God, for no one heareth, but in the Spirit he speaketh mysteries.”