John 9:6

6. He spat on the ground The Lord uses instrumentalities for the end, to show that the end was the purposed end, and not mere coincidence or chance. He uses instrumentalities plainly inadequate, to show that the power was miraculous. Both spittle and clay were often used by the ancients as an ointment for the cure of weak eyes; and this again indicates that our Lord purposes, by their use, to show that the cure is the result of his purpose. Yet no one could ever believe that the cure of one born blind could ever be effected naturally by such means. The cure was, therefore, an intended result and a miraculous one.

Made clay Made a clay mortar or mixture.