He further proceeds notably to interpret the language of the Gospel, In the beginning was the Word, and Life and Light, and The Word was made flesh, which had been misinterpreted by Eunomius; and overthrows his blasphemy, and shows that the dispensation of the Lord took place by loving-kindness, not by lack of power, and with the co-operation of the Father
But he puts his strength into his idle contention and says, “From the facts themselves, and from the oracles that are believed, I present the proof of my statement.” Such is his promise, but whether the arguments he advances bear out his professions, the discerning reader will of course consider. “The blessed John,” he says, “after saying that the Word was in the beginning, and after calling Him Life, and subsequently giving the Life the further title of 'Light,' says, a little later, 'And the Word was made flesh. ' If then the Light is Life, and the Word is Life, and the Word was made flesh, it thence becomes plain that the Light was incarnate.”
What then? Because the Light and the Life, and God and the Word, was manifested in flesh, does it follow that the true Light is divergent in any degree from the Light which is in the Father? Nay, it is attested by the Gospel that, even when it had place in darkness, the light remained unapproachable by the contrary element: for “the Light,” he says, “shined in darkness, and the darkness comprehended it not.” If then the light when it found place in darkness had been changed to its contrary, and overpowered by gloom, this would have been a strong argument in support of the view of those who wish to show how far inferior is this Light in comparison with that contemplated in the Father.
But if the Word, even though it be in the flesh, remains the Word, and if the Light, even though it shines in darkness, is no less Light, without admitting the fellowship of its contrary, and if the Life, even though it be in death, remains secure in Itself, and if God, even though He submit to take upon Him the form of a servant, does not Himself become a servant, but takes away the slavish subordination and absorbs it into lordship and royalty, making that which was human and lowly to become both Lord and Christ—if all this be so, how does he show by this argument variation of the Light to inferiority, when each Light has in equal measure the property of being inconvertible to evil, and unalterable?
And how is it that he also fails to observe this, that he who looked on the incarnate Word, Who was both Light and Life and God, recognized, through the glory which he saw, the Father of glory, and says, “We beheld His glory, the glory as of the Only-begotten of the Father”?
Source: Against Eunomius (New Advent)