Moses made a bronze snake and put it on the pole; if a snake had bitten someone, then, when he looked toward the bronze snake, he stayed alive…On this verse the Ramban comments that "it is the way of the Torah to have miracles within miracles, with harm God removes harm, and heals illness with illness." While the Ramban tries to connect this verse with the (now outdated) science of his own day, the underlying principle remains. The snake, which frightens and kills human beings, is in the hands of God and his servants a tool of healing.