ויקחו בני אהרן נדב ואביהוא איש מחתתו
Yalkut Shemoni (Shemini, Remez 524) adds that each one – Nadav and Avihu – took his fire pan, mei’atzmo, on his own, neither discussing it with – nor accepting advice from – his brother. The two brothers erred in thinking that it was a mitzvah to offer on their own without first receiving a Divine mandate. It makes sense to assume that their error was extremely minute, as they were such righteous individuals. They certainly did not arrive at their individual decisions without intense cogitation. Clearly, they thought the matter through and rendered their individual decisions. Nonetheless, the Yalkut implies,…