5 “He that hates me,” He says, “hates my Father also.” Here it may be said to us, Who can hate one whom he knows not? And certainly before saying, “If I had not come and spoken unto them, they had not had sin,” He had said to His disciples, “These things will they do unto you, because they know not Him that sent me.” How, then, do they both know not, and hate? For if the notion they have formed of Him is not that which He is in Himself, but some unknown conjecture of their own, then certainly it is not Himself they are found to hate, but that figment which they devise or rather suspect in their error. And yet, were it not that men could hate that which they know not, the Truth would not have asserted both, namely, that they both know not, and hate His Father. But such a possibility, if by the Lord's help we are able to show it, cannot be demonstrated at present, as this discourse must now be brought to a close.
Source: Tractates on the Gospel of John (New Advent)