John 9:6

Ταῦτα εἰπὼν, i.e., “in this connection,” ἔπτυσε χαμαί … “He spat on the ground and made clay of the spittle,” “quia aqua ad manum non erat,” says Grotius; but that spittle was considered efficacious Lightfoot proves by an amusing anecdote and Wetstein by several citations. Tacitus (Hist., iv. 81) relates that the blind man who sought a cure from Vespasian begged “ut … oculorum orbes dignaretur respergere oris excremento”. Probably the idea was that the saliva was of the very substance of the person. Tylor (Prim. Culture, ii. 400) is of opinion the Roman Catholic priest's touching with his spittle the ears and nostrils of the infant at baptism is a survival of the custom in Pagan Rome in accordance with which the nurse touched with spittle the lips and forehead of the week-old child. Virtue was also attributed to clay in diseases of the eye. A physician of the time of Caracalla prescribes “turgentes oculos vili circumline coeno”. That Jesus supposed some virtue lay in the application of the clay is contradicted by the fact that in other cases of blindness He did not use it. See Mark 10:46. But if He applied the clay to encourage the man to believe, as is the likely solution, the question of accommodation arises (see Lücke). The whole process of which the man was the subject was apparently intended to deepen his faith.