Presenting his ‘credentials’ before Pharaoh, Moses threw down his staff before the Egyptian king, and it transformed into a viper. When the magicians of Egypt did the same with their magic, “the staff of Aaron swallowed up their staffs” (Ex. 7:12).
The Sages in Shabbat 97a noted that the Torah does not say that Aaron’s snake swallowed up the magicians’ staffs. It says Aaron’s staff did the swallowing. A double miracle, a “miracle within a miracle” occurred. The viper became a staff once again, and only then — as a staff — did it swallow up the other staffs. What is the significance of this double miracle?
Just as there is an underlying order in the world of nature, so too there is order and structure in the realm of miracles. We may distinguish between two types of laws of the natural world: those of a fundamental nature, and those that have a detailed and specific function. The extent to which a miracle defies natural law depends on the purpose of that divine intervention.
Sometimes it is sufficient to have a minor disruption, and still remain within the overall system of natural law. For example, when the prophet Elisha advised the widow in debt how to miraculously produce oil (II Kings 4:1-7), the oil was not created ex nihilo. Rather, the miracle was based on an existing jar of oil. There occurred no blatant abrogation of the laws of nature; they were merely ‘extended,’ as the small cruse of oil sufficed to fill up many large pots. But the basic framework of natural law was left undisturbed.
The purpose of Elisha’s miracle was to help out a poor woman in need. The goal of Moses’ miraculous signs in Egypt, on the other hand, was far more grandiose. These wonders were meant to demonstrate the power and greatness of the Creator, “so that you will know that I am God here on earth” (Ex. 8:18).
In Egypt, God willed to demonstrate His ability to overrule any law and limitation of the natural world. Therefore, it was necessary to have a “miracle within a miracle.” This exhibited independence and autonomy at all levels of natural law, both specific and fundamental. The miracle of the staff occurred not only as a minor disruption of nature — a level at which the Egyptian magicians could also function — but also at the level of total disregard for the most basic laws of nature, so that one staff could “swallow up” other staffs.
(Gold from the Land of Israel pp. 108-109. Adapted from Ein Eyah vol. IV, pp. 243-4)