If any man will do his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself.
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Cyril of Alexandria
We ought uncritically and without all doubt to receive the words of the Truth, and to believe that a thing once said, cannot be otherwise than as it was declared to be. But He permits not His saying to be without proof, on account of the unbelievers, but introduces a most evident and exceeding clear solution, tempering with much skill the fashion of His words. And what the skill is, what the order of the economy, we will again say. They were seeking to kill Him on account of the paralytic, him (I mean) that was healed on the sabbath day. Gently then does He alike scare them from their dreadful purpose against Him, and clearly does He convict those who are travailing with their blood-thirsty purpose against Him, that they were choosing to fulfil their own lust rather than the will of the Law-giver. For then (saith He) shall ye know perfectly of My doctrine, that it is of God the Father, when ye shall choose to follow His Will rather than your own. But the Will of the Law-giver and of God, is to abstain wholly from murder. Then, then (He saith) shall ye, not holden beforehand by unjust hatred, nor thrust forth in brutish guise to no seasonable anger, know clearly, whether the word of My teaching is of God, or whether I am speaking of Myself. Having therefore interwoven reproof with profit, He with justice accuses them, for that they unreasonably mock at what He teaches, though God the Father consenteth and co-willeth, or what also is true, co-teacheth and co-interpreteth. But He puts Of Myself, for, Privately and wholly severed from being after the Co-Will and Purpose of the Father. And I do not suppose any person of sound mind will think that He accuses His own words of being spurious, but says that they will never be otherwise than in accordance with the Will of God the Father. For He speaks by His own Word and Wisdom, His Own Offspring; but That speaks not at all diversely from Himself, for how could It?