The features of Moses are the features of the microcosm [ze'ir anpin], while Aaron symbolizes the angel Michael, the great minister [of Divine will] who presents the souls of the righteous to the Holy One blessed be He. It is known that the souls of those deceased in the Land of Israel are elevated by an angel of mercy, of those angels appointed by Michael's hand, though this quality is for the simple folk living in the Land.
The righteous are indeed [elevated] by the angel Michael, and with him is the revelation of the Shechina, as we find in the case of our Teacher, Moses, may he rest in peace, when the Holy One blessed be He said unto Michael: Go forth and bring me the soul of Moses, and although that was not the instance of his death, which happened later by a kiss by G-d, one may say, as concerns Moses, that he could not be touched by anyone, neither by any angel nor seraph, except by the Holy One blessed be He, in His Glory; since he [Moses] was equated to [the people of ] Israel in its entirety, as they wrote: 'Out one woman's belly were six hundred thousand born' and also because it hints to ze'ir anpin – meaning: for inwardness, as is written in the holy Zohar: Moses towards the interior and Aaron towards the exterior, and if, concerning the aspect of our father Jacob, may he rest in peace, they said he is considered as towards the exterior, regarding Moses, all the more so as concerns all other righteous ones, who are the sons of his sons, and are referred to as 'towards the exterior' regarding Moses, and their demise is by the angel Michael.