John Lightfoot on Matthew 8:3

[Jesus touched him.] It was indeed a wonder, that when the leprosy was a creeping infection, the priest, when he judged of it, was not hurt with the infection. It cannot be passed over without observation, that Aaron, being bound under the same guilt with Miriam, bore not the same punishment: for she was touched with leprosy, he not, Numbers 12. And also that Uzziah should be confuted concerning his encroaching upon the priesthood no other way than by the plague of leprosy. In him God would magnify the priesthood, that was to judge of the leprosy; and he would shew the other was no priest, by his being touched with the leprosy. It can scarcely be denied, indeed, that the priests sometimes might be touched with that plague; but certainly they catched not the contagion while they were doing their office in judging of it. This is a noble doctrine of our High Priest, the Judge and Physician of our leprosy, while he remains wholly untouched by it. How much does he surpass that miracle of the Levitical priesthood! They were not touched by the contagion when they touched the leprous person; he, by his touch, heals him that hath the infection.