Comentario sobre Exodo 7:12

ויבלע מטה אהרן BUT AARON’S STAFF SWALLOWED (It states that the staff swallowed) — after it had again become a staff it swallowed all of them (Shabbat 97 a; Exodus Rabbah 9:7).

ויהיו לתנינים, they looked and felt like these kinds of monsters. They were not able to move like these monsters move, or even not at all.

ויהיו לתנינם, “they (the staffs of the sorcerers) turned into snakes.” The Torah refrained from saying ויהיו תנינים, which would have meant that they actually became snakes. The sorcerers did not have the power to do that. They could only create the illusion not the real thing. The wording of the Torah here is similar to Joshua 7,5: “their hearts melted into water.” This was a description of people losing courage. It did not describe a phenomenon literally. We have another example of this in (Samuel I 25,37) וימת לבו בקרבו והוא היה לאבן, which translated literally would mean “his heart (Naval’s) died within him, and it turned into stone.” The word אבן is merely a figure of speech.
You may well counter that the expression ויהי לתנין is also used when Moses’ staff turned into a snake, so what is so peculiar about the Torah not writing תנין when describing what happened to the staffs of the sorcerers? We have to explain that in the case of Moses’ i.e. Aaron’s staff, this was a true transformation of the staff into a snake and that a similar wording is found in Genesis 2,7 ויהי האדם לנפש חיה where the letter ל at the beginning of the word לנפש certainly does not speak about something illusory. However, by way of contrast, what the sorcerers did was merely sleight of hand. Seeing that the wording lent itself to two different interpretations, the Torah had to write immediately that Aaron’s staff swallowed all the staffs of the sorcerers in order the show the qualitative difference between what Aaron had done and what the Egyptians had been able to do. The fact that the Torah describes “their staffs” as being swallowed instead of “their snakes” being swallowed, shows that their staffs had remained staffs in spite of appearing to be snakes. Another proof that the sorcerers only created an illusion is that the Torah does not describe them as having performed their art in the presence of Pharaoh and his servants as the Torah had been at pains to emphasise concerning Moses’ miracle.
Alternatively, supposing that the חרטומים had really been capable of turning their staffs into snakes as the Talmud Chulin 7 suggests, why then were they called sorcerers instead of prophets? The answer is that they denied the power of the celestial forces. We could interpret the words ויהיו לתנינים to mean that their staffs did indeed turn into live snakes. The letter ל would be justified seeing that later on these snakes reverted to being staffs. The qualitative edge of Moses’ staff was simply that it swallowed the staffs of the sorcerers. According to Shemot Rabbah 9,7 when Pharaoh observed that Moses’ staff (as a staff) was able to swallow the combined staffs of his sorcerers he reflected that it might equally be capable of swallowing him and his throne. The word ויבלע means that something inert was able to swallow both something else inert and something live. We have a parallel in Numbers 16,32 when the earth swallowed both Korach and family as well as his tents and belongings.