We understand that the Torah speaks only about a person’s internal attributes that require correction. Among them there are attributes that are cut and eaten afterward, and also attributes and desires that are burnt, drowned, buried, or strangled.
In other words, there are a thousand ways to fight a person’s egoistic desires that are seemingly expressed in such external actions that are really scary. But in fact, these are all internal actions that are expressed that way in matter.
Like Aaron, his sons are our highest internal attributes, and what is more Aaron’s sons are greater than Aaron since a son is the next higher level. For example, we constantly see Rabbi Elazar who is Rabbi Shimon’s son next to Rabbi Shimon who wrote The Book of Zohar.
So if the attribute of Rabbi Shimon refers to a person’s correction, the attribute of Elazar, being a higher level, refers to the correction of the whole world.
Aaron is the highest level of love and bestowal and this is the reason he is called a priest. Two branches stem from him, his two sons, Nadav and Avihu. The two branches that connect in a person believe that they can raise special incense, which means to perform a correction and to ascend to the highest level with their fire. But this is impossible until the end of correction. Therefore, the attribute of Nadav and Avihu in a person have to be put to death for the time being, concealed, and not be allowed to be used.
To enter with their fire means that a person can operate on the attribute of bestowal by himself, which means to receive in order to bestow and to mutually cooperate with the Light of Hochma. He can also reflect Light himself, but this is impossible before entering the land of Israel.
From KabTV’s “Secrets of the Eternal Book” 3/6/14