וַיֹּאמֶר מֹשֶׁה אֶל אַהֲרֹן הוּא אֲשֶׁר דִּבֶּר ה' לֵאמֹר בִּקְרֹבַי אֶקָּדֵשׁ וְעַל פְּנֵי כָל הָעָם אֶכָּבֵד
Then Moses said to Aaron, This is what the Lord spoke, saying, I will be sanctified in them that come near to me, and before all the people I will be glorified. (Leviticus 10:3)
Our master explained that the meaning of this verse is that a person can achieve moral perfection only by learning to simultaneously love and fear the Eternal, so that his love of and his fear for the Eternal grow stronger in equal measure. As the Psalmist says (Psalms 2:11): "Serve the Lord with fear and rejoice with trembling" (עִבְדוּ אֶת ה' בְּיִרְאָה וְגִילוּ בִּרְעָדָה). Thus, any commandment that is not performed with both trepidation and love lacks the two wings with which to ascend upward. And should a burning love inflame someone to transgress an ordinance (חק) in order to approach the Eternal too closely, it is fear that must cause him to draw back. For many have been brought down because their love for G-d caused them to approach Him too closely.
So, too, did Nadav and Avihu sin by approaching too closely the inner sanctum of the Eternal. As the wise commentators have written, they dared, owing to the intensity of their love for the Eternal, to ascend bareheaded before Him, removing the veil of fear from their faces, and, as a consequence, they died. From this incident, the great and wise ones of the nation, who are closest to G-d, drew the lesson that they dare not ascend to the Eternal lest they be consumed by fire, as were these two pious and exceedingly righteous ones who died so suddenly. But the simple people of the nation, who do not really understand what love of the Eternal entails, took the opposite lesson: to serve G-d with joy and a good heart, to love Him and to cling to Him, because they saw how precious it is, in the eyes of the Eternal, to worship Him with love and not with indifference. For if it were not for their indifference, these righteous ones, with a great and surpassing love, surely (the simple people suppose) would not have stumbled, and no ill would have befallen them.
Thus, holiness causes fear - fear of exaltation and anxiety at holiness, as it is written (Leviticus 19:30) "and fear my sanctuary" (וּמִקְדָּשִׁי תִּירָאוּ). But honor and glory are a sign of love, because one gives honor to that which he loves, as the Sages say in the Talmud, explaining why in the commandment to "honor thy father and thy mother" "father" precedes "mother." [Since the natural inclination is to love one's mother more than one's father, it was necessary to underscore the duty to honor one's father by mentioning the father first.] It is therefore written "this is what the Lord spoke I will be sanctified in them that come near to me" (הוּא אֲשֶׁר דִּבֶּר ה' בִּקְרֹבַי אֶקָּדֵשׁ). That is to say, because of this incident, those that are close to the Eternal and cling to Him will become sanctified and reverential in fearing Him. However, "and before all the people I will be glorified" (וְעַל פְּנֵי כָל הָעָם אֶכָּבֵד). In other words, because the ordinary people (who are not so close to the Eternal) will learn from the incident to love Me and, as a result, I will be honored in their midst.
And Aaron held his peace (Leviticus 10:3)
In Midrash Rabbah it is asked: What could Aaron have said? "On the eighth day the flesh of his foreskin shall be circumcised" (וביום השמיני ימול בשר ערלתו).
This remark is an astonishing mystery. But we heard from the holy mouth of our master a correct explanation which he said in the name of his father the gaon (R. Avraham Glasner, 1826-78). The law is that if a woman's first two sons died after being circumcised, the third son may not be circumcised, because there is a presumption that circumcision would endanger the life of any subsequent sons that are born. Thus, when the two sons of Aaron were killed because they approached the Eternal to perform a service, the danger to Aaron's sons had been confirmed, and Aaron could have broken the chains of the priesthood that were upon him and said, "behold I am going to die because of it." Since he could have used the law of circumcision to support his position, but instead remained quiet, he was rewarded.
וַיִּקְצֹף עַל אֶלְעָזָר וְעַל אִיתָמָר
And he was angry with Eleazar and Ithamar (Leviticus 10:16)
The Midrash Rabbah (Leviticus 13:1) comments: In three instances did Moses lose his temper and [in consequence] a law escaped his memory [on each occasion], and the following are the instances: In respect of the Sabbath, of metal utensils, and of an onen (i.e., whether the sin-offering of Aaron could be eaten by an onen).
Many have objected that here in the incident of the sin-offering of Aaron, the order was reversed, because Moses became angry only because he erred in his halakhic ruling. See the Sifra which records an opinion that disputes the premise that Moses erred because of his anger and asserts rather that Moses became angry because he erred.
However, the Midrash appears unobjectionable to our master, because a wise and understanding person is not quick to respond and will not say anything until he has weighed carefully whether it correct. Should an incorrect idea occur to such a person, he would therefore certainly reconsider it before saying it out loud. Scientists have, in this manner, broken down every thought that leads to some action into four components: conception (מחשבה פשוטה), reflection (התבוננות), affirmation (הסכמה), and finally speech or action. Thus, as soon as Moses conceived the thought (מחשבה פשוטה) that Aaron had acted improperly, he became angry, which caused his reflection (התבוננות) and affirmation (הסכמה) to be in error. The Midrash therefore correctly attributed his mistake to anger, because it was only because of his anger that he mentally affirmed the initial idea that he had wrongly conceived.