"Then, seeking a way to let the word that exists in me reach you and dwell with you, I have recourse to my voice. Its sound communicates my word and its meaning to you. When it is finished it vanishes. But my word, is now in you, without ever having left me."
-- Sermon 293, 3
This is deep.
Augustine (AD 354-430) was a rhetorician by training, so he always had a passionate love for words. In his magisterial De Triniatate (On the Trinity), Augustine, on the biblical supposition that humans are made in the image of God, looked at a number of human psyhcological and spiritual faculties as windows into the nature of the Triune God. One of these faculties he examined was speech, specifically the relation between thought, will and speech.
This quote from Sermon 293 captures his thesis about speech as a window to God's nature. The Father has the eternal thought of the Word of life and love, which therefore coexists with the Father as one with His mind. The procession of the Holy Spirit is from the Father by, from and through that selfsame Word. The key is that while all three things are hypostatically distinct -- pure concept, verbal concept, spoken concept -- they are all essentially one thing and rooted co-equally in the same Being. The words you say stem from the words you think which had already stemmed from the thoughts you have.
What is even more exciting is that, in the last sentence, Augutine very powerfully illustrates the indwelling of the Holy Spirit in Christians. God speaks His Word of love to us by the Holy Spirit (and thus sends His Spirit, Breath, ruach, to us by that Word), and that Word dwells in us by Spirit just as dynamically, albeit contingently, as it does in the Father!
Prayer. I ask you, my God, to reveal me to myself.
-- Confessions 10, 1