On The Holy Trinity by St. Augustine
Chapter 2.--How We are Rendered Apt for the Perception of Truth Through the Incarnate Word.
4. But |the light shineth in darkness, and the darkness comprehended it not.| Now the |darkness| is the foolish minds of men, made blind by vicious desires and unbelief. And that the Word, by whom all things were made, might care for these and heal them, |The Word was made flesh, and dwelt among us.| For our enlightening is the partaking of the Word, namely, of that life which is the light of men. But for this partaking we were utterly unfit, and fell short of it, on account of the uncleanness of sins. Therefore we were to be cleansed. And further, the one cleansing of the unrighteous and of the proud is the blood of the Righteous One, and the humbling of God Himself; that we might be cleansed through Him, made as He was what we are by nature, and what we are not by sin, that we might contemplate God, which by nature we are not. For by nature we are not God: by nature we are men, by sin we are not righteous. Wherefore God, made a righteous man, interceded with God for man the sinner. For the sinner is not congruous to the righteous, but man is congruous to man. By joining therefore to us the likeness of His humanity, He took away the unlikeness of our unrighteousness; and by being made partaker of our mortality, He made us partakers of His divinity. For the death of the sinner springing from the necessity of comdemnation is deservedly abolished by the death of the Righteous One springing from the free choice of His compassion, while His single [death and resurrection] answers to our double [death and resurrection]. For this congruity, or suitableness, or concord, or consonance, or whatever more appropriate word there may be, whereby one is [united] to two, is of great weight in all compacting, or better, perhaps, co-adaptation, of the creature. For (as it just occurs to me) what I mean is precisely that co-adaptation which the Greeks call harmonia. However this is not the place to set forth the power of that consonance of single to double which is found especially in us, and which is naturally so implanted in us (and by whom, except by Him who created us?), that not even the ignorant can fail to perceive it, whether when singing themselves or hearing others. For by this it is that treble and bass voices are in harmony, so that any one who in his note departs from it, offends extremely, not only trained skill, of which the most part of men are devoid, but the very sense of hearing. To demonstrate this, needs no doubt a long discourse; but any one who knows it, may make it plain to the very ear in a rightly ordered monochord.