מדרש על במדבר 17:25

(Deut. 3:24:) YOU HAVE <ONLY> BEGUN <TO SHOW YOUR SERVANT YOUR GREATNESS AND YOUR MIGHT…. > He said to him: You are the one who opened a door for me to pray to you.³Sifre to Deut. 3:24 (27). When? When they did that deed.⁴I.e., when they made and worshiped the golden calf. See Deut. 9:7–12. The Holy One said to him (in Deut. 9:14): LET ME ALONE, AND I WILL DESTROY THEM AND BLOT OUT THEIR NAME FROM UNDER THE HEAVENS. Moses said: Who would seize hold of the Holy One? One only seeks to pray for one's children. What is written there (in Exod. 32:11)? AND MOSES IMPLORED THE LORD HIS GOD. Moses said: Once I prayed for the community and was answered, but the community prayed for me and was not answered. Why? Because you have issued a decree over me <for calling them rebels>! But you were the one who began by calling them <rebels> (in Numb. 17:25 [10]): <PUT BACK AARON'S ROD … > TO BE KEPT AS A SIGN FOR THE CHILDREN OF REBELLION. Then because I called them <rebels> (in Numb. 20:10): LISTEN, YOU REBELS, you said (in 20:12): THEREFORE YOU SHALL NOT LEAD THIS CONGREGATION <INTO THE LAND THAT I HAVE GIVEN THEM>.

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And Moses said unto Aaron: “Take a jar and put an omerful of manna therein” (Exod. 16:33). I would not know of what substance the jar was fashioned, whether of silver or of gold or of iron or of lead, except for the fact that Scripture says tzintzenet, a word that suggests something that keeps a thing cooler than anything else.¹⁴Jastrow tells us that tzintzenet is in the text because it glistened more than any other thing (i.e., it was a glazed earthen vessel). And that could only be a clay vessel. And put an omerful of manna therein. R. Eleazar held: It was stored there for future generations. While R. Eliezer was of the opinion that it was put there for the Messianic era, for the time about which the prophet Jeremiah said to Israel: Why do you not devote yourself to the Torah? And they replied: If we do, how shall we obtain our sustenance? Then they brought forth the jar of manna and said: O generation; see the word of the Lord: Have I been a wilderness unto Israel? or a land of thick darkness? Wherefore say My people: “We roam at large; we will come no more unto Thee?” (Jer. 2:31). Your fathers occupied themselves with the Law, and see how they were fed; concern yourselves with the Law, and I shall feed you from this jar. This is one of the three things that Elijah will restore to Israel in the future: the jar of manna, the bottle of anointing oil, and the bottle of sprinkling water. Others add, Aaron’s rod with its ripe almonds and blossoms, as is said: Put back the rod of Aaron before the testimony, to be kept there, for a token against rebellious children (Num. 17:25).

(Exodus 16:33) "And Moses said to Aaron: Take one tzintzeneth": I would not know what it is — whether of silver, or iron, or lead, or copper, or tin. It is, therefore, written "tzintzeneth" — something that can be seen through ("metztith"), i.e., an earthenware vessel (from which glass is made). "and put therein a full omer of manna and place it before the L rd as a keeping for your generations": R. Yehoshua says: for the fathers (i.e., for those of that generation). R. Eliezer says: for the days of the prophet Jeremiah. For when Jeremiah said to Israel: Why are you not studying Torah, they said to him: How will we feed ourselves? He took out the flask of manna and said to them (Jeremiah 2:31) "O generation, see the word of the L-td, etc." Your fathers, who studied Torah, see how they were fed. You, too, if you study Torah, the Holy One Blessed be He will feed you of this. And this is one of the three things that Eliyahu is destined to present to Israel: the flask of manna, the flask of the sprinkling waters (viz. Numbers 19:9), and the flask of the anointing oil, (viz. Exodus 30:31). Others say: Also the staff of Aaron, its almonds and its blossoms, (viz. Numbers 17:25).