Les Nombres 33:31 Midrash : Mekhilta DeRabbi Yishmael & Midrash Tanchuma Buber

And thus we find that they went back (the distance of) three journeys (at Moses' behest), viz. (Numbers 33:8-10) "And they journeyed from Pi Hachiroth … And they journeyed from Marah and they came to Eilim … And they journeyed from Eilim and they encamped at the Red Sea." And thus we find that they went back eight journeys in honor of Aaron for his burial. As it is written (Devarim 10:6) "And the children of Israel journeyed from Be'eroth Benei Yaakan … There Aaron died, etc," Now did Aaron die in Mosera? Did he not die in Hor Hahar, viz. (Numbers 33:38) "And Aaron the Cohein went up to Hor Hahar, etc."? What, then, is the intent of "There Aaron died and he was buried there"? We are hereby apprised that they went back eight journeys in honor of Aaron for his burial, viz. (Numbers 33:31-37) "And they journeyed from Moseroth and they encamped in Benei Yaakan. And they journeyed from Bnei Yaakan and they encamped in Chor Hagidgad and they encamped in Yatvatha. And they journeyed from Yatvatha and they encamped in Avronah. And they journeyed from Avronah and they encamped in Etzyon Gaver. And they journeyed from Etzyon aver and they encamped in the desert of Sin, which is Kadesh. And they journeyed from Kadesh and they encamped in Hor Hahar, at the edge of the land of Edom."

(Numb. 21:1, cont.:) HE FOUGHT AGAINST ISRAEL. <That king> was Amalek. Why did < Scripture > call him a Canaanite? Because because Israel was forbidden to fight with the children of Esau, of whom it is stated (in Deut. 2:5): DO NOT ENGAGE THEM IN BATTLE. When Amalek came and engaged in battle with them a first time and a second, the Holy One said to them: This <nation> is not forbidden like the the children of Esau. Just look. They are like Canaanites, of whom it is stated (in Deut. 20:17): NO, YOU SHALL UTTERLY DESTROY THEM: THE HITTITES, THE AMORITES, THE CANAANITES, [….] For that reason he was called a Canaanite; and from time immemorial Amalek has been a {scourge} [strap] for the punishment of Israel. You find that, when Aaron died, Amalek went out against them; and Israel retreated back seven stages <of their journey>. Thus it is stated (in Deut. 10:6): THEN FROM THE WELLS OF BENE-JAAKAN THE CHILDREN OF ISRAEL JOURNEYED TO MOSERAH. THERE AARON DIED…. Did Aaron die there? Did he not die on Mount Hor, as stated (in Numb. 20:28) AND AARON DIED THERE ON THE SUMMIT OF THE MOUNTAIN?¹⁷²yYoma 1:1 (38ab); ySot. 1:10 (17d); cf. Mekhilta deRabbi Ishmael, Wayassa‘ 1, on Exod. 15:22. The verses are evidence of seven stages backwards (from Mount Hor to Moserah)¹⁷³Cf. Numb. 33:31-37, which lists the seven stages, but in the opposite direction. to teach you that <Israel> had retreated.