Why does the Torah insert the (otherwise superfluous) word "ve?Eileh Sh'mos B?nei Aharon"?
Seforno: Refer to 1:2:4:2.
What is the significance of the P'sik (the stroke) between the words "ha'Bechor" and "Nadav"?
Ba'al ha'Turim: To teach us that the word "B'chor" pertains to Aharon, who was the B'chor of Moshe 1 , and not to Nadav who died without children - and whose Bechorah was therefore ineffective.
Etz Yosef (in Bamidbar Rabah 6:2): He was older than Moshe, but not the B'chor, since Sh'mos Rabah (1:13) states that Miriam was two years older than Aharon. ("Vateiled le'Amram es Aharon ve'es Moshe ve'es Miriam" in 26:59 implies that Aharon was older. However, it seems that they were not born in this order. Did Moshe have another sister who brought Yocheved to Bisya (Sh'mos 2:7,8), and the Torah does not mention her again?! - PF)
