Against Praxeas by Tertullian
Chapter V.--The Evolution of the Son or Word of God from the Father by a Divine Procession Illustrated by the Operation of the Human Thought and Consciousness.
But since they will have the Two to be but One, so that the Father shall be deemed to be the same as the Son, it is only right that the whole question respecting the Son should be examined, as to whether He exists, and who He is and the mode of His existence. Thus shall the truth itself secure its own sanction from the Scriptures, and the interpretations which guard them. There are some who allege that even Genesis opens thus in Hebrew: |In the beginning God made for Himself a Son.| As there is no ground for this, I am led to other arguments derived from God's own dispensation, in which He existed before the creation of the world, up to the generation of the Son. For before all things God was alone -- being in Himself and for Himself universe, and space, and all things. Moreover, He was alone, because there was nothing external to Him but Himself. Yet even not then was He alone; for He had with Him that which He possessed in Himself, that is to say, His own Reason. For God is rational, and Reason was first in Him; and so all things were from Himself. This Reason is His own Thought (or Consciousness) which the Greeks call logos, by which term we also designate Word or Discourse and therefore it is now usual with our people, owing to the mere simple interpretation of the term, to say that the Word was in the beginning with God; although it would be more suitable to regard Reason as the more ancient; because God had not Word from the beginning, but He had Reason even before the beginning; because also Word itself consists of Reason, which it thus proves to have been the prior existence as being its own substance. Not that this distinction is of any practical moment. For although God had not yet sent out His Word, He still had Him within Himself, both in company with and included within His very Reason, as He silently planned and arranged within Himself everything which He was afterwards about to utter through His Word. Now, whilst He was thus planning and arranging with His own Reason, He was actually causing that to become Word which He was dealing with in the way of Word or Discourse. And that you may the more readily understand this, consider first of all, from your own self, who are made |in the image and likeness of God,| for what purpose it is that you also possess reason in yourself, who are a rational creature, as being not only made by a rational Artificer, but actually animated out of His substance. Observe, then, that when you are silently conversing with yourself, this very process is carried on within you by your reason, which meets you with a word at every movement of your thought, at every impulse of your conception. Whatever you think, there is a word; whatever you conceive, there is reason. You must needs speak it in your mind; and while you are speaking, you admit speech as an interlocutor with you, involved in which there is this very reason, whereby, while in thought you are holding converse with your word, you are (by reciprocal action) producing thought by means of that converse with your word. Thus, in a certain sense, the word is a second person within you, through which in thinking you utter speech, and through which also, (by reciprocity of process,) in uttering speech you generate thought. The word is itself a different thing from yourself. Now how much more fully is all this transacted in God, whose image and likeness even you are regarded as being, inasmuch as He has reason within Himself even while He is silent, and involved in that Reason His Word! I may therefore without rashness first lay this down (as a fixed principle) that even then before the creation of the universe God was not alone, since He had within Himself both Reason, and, inherent in Reason, His Word, which He made second to Himself by agitating it within Himself.