Comentario sobre Exodo 7:23

גם לזאת [NEITHER DID HE SET HIS HEART] TO THIS ALSO — to the wonder of the staff which was changed into a serpent and also not to that of the blood.

NEITHER DID HE SET HIS HEART TO THIS ALSO. I.e., to the wonder of the rod turning into a serpent,¹²⁸Above, Verse 10. nor to that of the waters turning into blood. [Thus the language of Rashi.] A more correct interpretation would appear to be that to this also means “to this also which was indeed a plague,” [as distinguished from the wonder of the rod turning into a serpent, which was not a plague at all], and he should have feared lest the power of G-d be upon him from now on.¹²⁹See Ramban above in Verse 16, where he explains that beginning with the wonder of the rod, Pharaoh already began fearing the coming of the plagues. It is this then which Scripture says here: In spite of his fear which he already had then even before the plagues came, “also” now that the first plague did come and he should have feared the coming of other plagues, yet he did not set his heart to it.

גם לזאת, seeing he had already made himself obstinate, vayechezak, (verse 13) at this time also, he relied on his own resources of self confidence to ignore what he had seen. However, when it came to the plague of frogs Pharaoh already began to waver and external stimuli in stiffening his attitude were required. Hence we read there (8,11) vayachbed Paroh et libbo, that Pharaoh had to draw on external stimuli to maintain his obstinate pose. The same was true with the fourth plague, that of the wild beasts invading civilised urban regions. (8,28)