Gregory the Great
Catena Aurea · Johannesevangelium 15
If I had not come and spoken unto them, they had not had sin: but now they have no cloke for their sin. He that hateth me hateth my Father also. If I had not done among them the works which none other man did, they had not had sin: but now have they both seen and hated both me and my Father. But this cometh to pass, that the word might be fulfilled that is written in their law, They hated me without a cause.
(xxv. Moral.) It is one thing not to do good, another to hate the teacher of goodness; as there is a difference between sudden and deliberate sins. Our state generally is that we love what is good, but from infirmity cannot perform it. But to sin of set purpose, is neither to do nor to love what is good. As then it is sometimes a heavier offence to love than to do, so is it more wicked to hate justice than not to do it. There are some in the Church, who not only do not do what is good, but even persecute it, and hate in others what they neglect to do themselves. The sin of these men is not that of infirmity or ignorance, but deliberate wilful sin.