8 But let us see what advantage it is that these words have sounded, “In the beginning was the Word, and the Word was with God, and the Word was God.” We also uttered words when we spoke. Was it such a word that was with God? Did not those words which we uttered sound and pass away? Did God's Word, then, sound and come to an end? If so, how were all things made by it, and without it was nothing made? How is that which it created ruled by it, if it sounded and passed away?
What sort of a word, then, is that which is both uttered and passes not away? Give ear, my beloved, it is a great matter. By everyday talk, words here become despicable to us, because through their sounding and passing away they are despised, and seem nothing but words. But there is a word in the man himself which remains within; for the sound proceeds from the mouth. There is a word which is spoken in a truly spiritual manner, that which you understand from the sound, not the sound itself.
Mark, I speak a word when I say “God.” How short the word which I have spoken— four letters and two syllables! Is this all that God is, four letters and two syllables? Or is that which is signified as costly as the word is paltry? What took place in your heart when you heard, “God”? What took place in my heart when I said “God”? A certain great and perfect substance was in our thoughts, transcending every changeable creature of flesh or of soul. And if I say to you, “Is God changeable or unchangeable?” you will answer immediately, “Far be it from me either to believe or imagine that God is changeable: God is unchangeable.”
Your soul, though small, though perhaps still carnal, could not answer me otherwise than that God is unchangeable: but every creature is changeable; how then were you able to enter, by a glance of your spirit, into that which is above the creature, so as confidently to answer me, “God is unchangeable”? What, then, is that in your heart, when you think of a certain substance, living, eternal, all-powerful, infinite, everywhere present, everywhere whole, nowhere shut in? When you think of these qualities, this is the word concerning God in your heart.
But is this that sound which consists of four letters and two syllables? Therefore, whatever things are spoken and pass away are sounds, are letters, are syllables. His word which sounds passes away; but that which the sound signified, and was in the speaker as he thought of it, and in the hearer as he understood it, that remains while the sounds pass away.
Source: Tractates on the Gospel of John (New Advent)