What was special about Moshe's staff?
Seforno: Although it was made out of ordinary wood, Hashem sanctified it to act as a sign on behalf of Moshe.
Targum Yonasan (on Pasuk 20): The staff, which Moshe plucked from Yisro's garden, 1 was made of sapphire taken from Hashem's precious Throne and weighed forty Sa'ah.
What was the significance of the staff? Why did Hashem instruct Moshe to take it with him on his Sh'lichus?
Seforno: It was a stick of rulership, the medium through which Moshe was able to override the laws of nature via his command.
Bearing in mind that Hashem had only performed one sign to date (See earlier, Pasuk 4), to which signs is Hashem referring here?
Rashi (in Pasuk 21) and Ramban #1: To the signs that He would teach him shortly. 1
Ramban #2: When earlier in the Parshah (Shemos 3:2), Hashem referred to all the wonders that He would perform in the midst of Egypt, He presumably told him what they were. And those are the signs that He is referring to here. 2