“The Lord said to Moses: When you go back to Egypt, see all the wonders that I have placed in your hand and perform them before Pharaoh; but I will harden his heart, and he will not let the people go” (Exodus 4:21). “The Lord said to Moses: When you go…” Of which wonder did He speak? If you say it is regarding the serpent, the leprosy, and the blood; didn’t the Holy One blessed be He say to him to perform them only for Israel?
Moreover, we do not find that Moses performed those signs before Pharaoh. Rather, what is “all the wonders that I have placed in your hand”? This is the staff upon which all ten plagues were written in acronym form, as detzakh adash be’aḥav.7This is an acronym of the initials of the plagues: Blood [dam], frogs [tzefarde’a], lice [kinnim] – detzakh; wild beasts [arov], pestilence [dever], boils [shekhin] – adash; hail [barad], locusts [arbeh], darkness [ḥoshekh], firstborn [bekhorot] – be’aḥav.
The Holy One blessed be He said to him: These are the plagues that I have placed in your hand. Perform them before Pharaoh with this staff.