Translations of kabbalistic texts are by Rabbi Larry Tabick, The Aura of Torah. Translations of the Torah and other commentaries are from Sefaria, except where otherwise noted.
After Moses’ complaint to God in the last parshah, God reassures Moses that he has heard the moaning of the people and provides more specific guidance to Moses on how to approach Pharaoh.
Tabick Translation: “For Pharaoh will say to you: ‘Perform a sign for yourselves.'”
JPS (Sefaria) Translation: The LORD said to Moses and Aaron, “When Pharaoh speaks to you and says, ‘Produce your marvel'”
כִּי֩ יְדַבֵּ֨ר אֲלֵכֶ֤ם פַּרְעֹה֙ לֵאמֹ֔ר תְּנ֥וּ לָכֶ֖ם מוֹפֵ֑ת וְאָמַרְתָּ֣ אֶֽל־אַהֲרֹ֗ן קַ֧ח אֶֽת־מַטְּךָ֛ וְהַשְׁלֵ֥ךְ לִפְנֵֽי־פַרְעֹ֖ה יְהִ֥י לְתַנִּֽין׃
The literal translation is to perform a wonder “for you.” The Pharaoh is not saying perform a wonder for me. Shalom Rokeach, the first Belzer rebbe, is puzzled by the literal meaning and provides an explanation.
Shalom Rokeach, 19th century Poland
It would seem that Scripture should have said, “Perform a sign for me.” That fact is, though, that “a fool has no desire for understanding” [Proverbs 18:2], as we find with King Ahaz, who said: “I will not ask or test the Eternal” (Isaiah 7:12). Therefore, on his own behalf, [Pharaoh] would not seek any sign at all. But, in his great wickedness, he was saying. “You yourselves do not perfectly and truly believe, so ‘perform a sign for yourselves.'”
One may add to this: It is written in books that there are righteous people who do not perform saving acts and there are righteous people, though only a few, who facilitate saving acts. The explanation is that, because of the lowliness of their spirit, they do not have complete faith and trust that they have the power to facilitate good and saving acts. And therefore they are unable to act in that way. Hence Pharaoh says: “Perform a sign for yourselves,” for you yourselves do not believe that you have the ability to perform a sign.
An earlier Hasidic text raises the same question:
Levi Yitzchak of Berdichex, writing in 18th century Ukraine.
at first glance the word לָכֶ֖ם used by the Pharaoh here was superfluous as Moses and Aaron did not need to identify themselves to each other. He should simply have said: “prove your mission by performing a miracle!” The Ariz’al (Rabbi Isaac Luria) writes that it is a rule that every human being is convinced that his words make a favourable impression on his Creator, and as a result further God’s dispensing of benefits to His people. Because of this belief in the power of speech, every person has to be extremely careful not to abuse this power of speech by talking nonsense, or worse. … The miracle was the result of Moses’ speaking to Aaron.
In other words, the Pharaoh is saying, “go ahead with your nonsense,” challenging Moses and Aaron to test their trust in God and each other. Remember that this verse is God predicting what Pharaoh will say. God, perhaps just having heard Moses’ complaint, is recognizing his vulnerability to Pharaoh undermining Moses’ trust in God and the Israelites.
How does our doubt create passivity? Why is it important for the righteous to act to facilitate good?