No man has seen God at any time; the only begotten Son, who is in the bosom of the Father, he has declared him.
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Hilary of Poitiers
AD 368
The Truth of His Nature did not seem sufficiently explained by the name of Son, unless, in addition, its peculiar force as proper to Him were expressed, so signifying its distinctness from all beside. For in that, besides Son, he calls Him also the Only-Begotten, he cut off altogether all suspicion of adoption, the Nature of the Only-Begotten guaranteeing the truth of the name.