9 Now because they did not thus consider these matters, the Ario-maniacs, being opponents of Christ, and heretics, smite Him who is their Helper with their tongue, and blaspheme Him who set [them] free, and hold all manner of different opinions against the Saviour. Because of His coming down, which was on behalf of man, they have denied His essential Godhead; and seeing that He came forth from the Virgin, they doubt His being truly the Son of God, and considering Him as become incarnate in time, they deny His eternity; and, looking upon Him as having suffered for us, they do not believe in Him as the incorruptible Son from the incorruptible Father.
And finally, because He endured for our sakes, they deny the things which concern His essential eternity; allowing the deed of the unthankful, these despise the Saviour, and offer Him insult instead of acknowledging His grace. To them may these words justly be addressed: Oh! unthankful opponent of Christ, altogether wicked, and the slayer of his Lord, mentally blind, and a Jew in his mind, had you understood the Scriptures, and listened to the saints, who said, 'Cause Your face to shine, and we shall be saved.' or again, 'Send out Your light and Your truth;'— then would you have known that the Lord did not descend for His own sake, but for ours; and for this reason, you would the more have admired His loving kindness.
And had you considered what the Father is, and what the Son, you would not have blasphemed the Son, as of a mutable nature. And had you understood His work of loving-kindness towards us, you would not have alienated the Son from the Father, nor have looked upon Him as a stranger, Who reconciled us to His Father. I know these [words] are grievous, not only to those who dispute with Christ, but also to the schismatics; for they are united together, as men of kindred feelings. For they have learned to rend the seamless coat of God: they think it not strange to divide the indivisible Son from the Father.
Source: Letters (New Advent)