Moshe said to Hashem in Parshas Shmini:
shlach NA (send please), who you will send
one vort:
he was referring to Nadav and Avihu, who Chazal say were greater than Moshe and Aharon.
NA meaning Nadav and Avihu (send Nadav and Avihu)
Nadav and Avihu, who were combined as a gilgul in NA, Navi Eliyahu, NA