Gregory the Great
Catena Aurea · Johannesevangelium 9
And as Jesus passed by, he saw a man which was blind from his birth. And his disciples asked him, saying, Master, who did sin, this man, or his parents, that he was born blind? Jesus answered, Neither hath this man sinned, nor his parents: but that the works of God should be made manifest in him. I must work the works of him that sent me, while it is day: the night cometh, when no man can work. As long as I am in the world, I am the light of the world. When he had thus spoken, he spat on the ground, and made clay of the spittle, and he anointed the eyes of the blind man with the clay, And said unto him, Go, wash in the pool of Siloam, (which is by interpretation, Sent.) He went his way therefore, and washed, and came seeing. Jesus answered, Neither hath this man sinned, nor his parents.
(viii. Moral. c. xxx. [49.]) Or thus: By His spittle understand the savour of inward contemplation. It runs down from the head into the mouth, and gives us the taste of revelation from the Divine splendour even in this life. The mixture of His spittle with clay is the mixture of supernatural grace, even the contemplation of Himself with our carnal knowledge, to the soul’s enlightenment, and restoration of the human understanding from its original blindness.