Midrasch zu Wajikra 11:1

1) "And He called to Moses and the L–rd spoke to him, etc." "to him" — to exclude Aaron. R. Yehudah b. Betheira said: Thirteen dibroth (accompanied by a command) were stated in the Torah to Moses and Aaron, and, corresponding to them, thirteen limitations, to teach us that they were not spoken to Aaron, but to Moses, to tell them to Aaron. (The dibroth: 1) [Shemoth 6:13]; 2) [Shemoth 7:8]; 3) [Shemoth 9:8]; 4) [Shemoth 12:1]; 5) [Shemoth 12:43]; 6) [Vayikra 11:1]; 7) [Vayikra 13:1]; 8) [Vayikra 14:33]; 9 [Vayikra 15:1]; 10 [Bamidbar 2:1]; 11 [Bamidbar 4:1]; 12 [Bamidbar 4:18]; 13) [Bamidbar 19:2].)

1) (Vayikra 11:1) "And the L–rd spoke to Moses and to Aaron to say to them": (to say) to the sons, to Elazar and Ithamar, or to say to Israel? "Speak to the children of Israel" (Vayikra 11:2) is the speaking to Israel. How, then, are we to understand "to say to them"? To say to the sons, to Elazar and to Ithamar.

2) "when they drew near before the L–rd and they died": R. Yossi Haglili says: They died because of the drawing near (and entering the holy of holies without permission), and not because of the incense offering. R. Akiva says: They died because of the offering and not because of the drawing near. One verse (our verse) states "when they drew near before the L–rd and they died," and another verse states (Vayikra 11:1) "and they offered before the L–rd a strange fire." The resolution (Bamidbar 3:4) "when they drew near (with) a strange fire before the L–rd" — They died because of the drawing near and not because of the offering. R. Elazar b. Azaryah says: The offering is sufficient (for death) unto itself, and the drawing near is sufficient unto itself.