Pharaoh remained unimpressed. Turning a staff into a snake was a feat easily repeated by Egyptian magicians (Exodus 7:11). And even after Moses’ snake swallowed up the magically crated ones, Pharaoh was unmoved. Turning water into blood fared no better. Pharaoh’s magicians repeated that feat as well (Exodus 7:22). And they were able to bring forth frogs as well. So much for the power of the Hebrews’ God. But when Pharaoh’s magician tried to reproduce the plague of gnats, they were unsuccessful (Exodus 8:14). It was then that they proclaimed: “This is the finger of God!” (Exodus 8:15). Though Pharaoh refused to let the Hebrew slaves go, the magicians seemed to understand the futility of resisting any longer. But was that really the case?
The classical medieval commentator Nahmanides explains that the magicians were not (yet) won over by this display of power. The magicians were minimizing the effect of the plague of lice explaining that it is “just a small thing;” entirely inconsequential. So, one might be led to conclude that Nahmanides understands that the magicians were encouraging Pharaoh to stubbornly hold out rather than surrender to Moses’ demand to release the slaves from Egyptian bondage.
However, a closer reading of Nahmanides reveals the opposite. The “finger of God” is the Torah’s way of expressing the magician’s concern that the Hebrew God is much too powerful for Pharaoh to confront because if the plague of gnats is what a mere finger can produce, what might a whole hand? (An echo of this interpretation is included in the Passover Haggadah. Each of Rabbi Yosi the Galilean, Rabbi Eliezer, and Rabbi Akiva argue that if one finger can bring about ten plagues in Egypt, then a whole hand can bring about 50, 200, or 250 plagues at the Red Sea.)
As a literary device, the role of the magicians is intended to show how those who dismissed the power of the Hebrew God came to recognize it. Theologically, the interplay of the magicians and Pharaoh is intended to show that God is able to perform feats that are simple beyond the capabilities of mere mortals. It is the omnipotent God of Israel who rules over all.