What did Nadav and Avihu do wrong?
Rashi #1 (in Pasuk 2, and Seforno #1 (both citing R. Eliezer in Eruvin, 63a): They issued a ruling in the presence of their Rebbe - Moshe. 1
Rashi #2 (in Pasuk 2, citing R. Yishmael in Eruvin, 63a) and Targum Yonasan #1: They drank wine 2 before entering the Mishkan. 3
Rashi #3 and Rashbam (in Acharei-Mos): They entered the Kodesh Kodshim without the Korbanos prescribed in the Parshah of Yom Kipur. 4
Rashi #4: Because following Aharon's participation in the Chet ha'Eigel, Hashem decreed that his sons should die. 5
Ramban (in Pasuk 2, according to Kabalah): They brought the Ketores to the Midas ha'Din, and not directly to Hashem. 6
Seforno and Ba'al ha'Turim: They brought private Ketores. which the Torah forbids. 7
Rashbam, Rosh (in Pasuk 2) and Da'as Zekenim: They brought human fire before fire from Heaven descended for the first time. 8 Once Heavenly fire descended, it was a Mitzvah to bring human fire but not beforehand.
Moshav Zekenim #1: They should have brought the Ketores directly on the Mizbe'ach, but they brought it on incense pans.
Refer to 1:7:151:2 and note.
Moshav Zekenim #2 (in 16:1, citing Vayikra Rabah 20:10): When Moshe and Aharon walked in front of them, they said 'When these two elders die, 9 we will have authority over the Tzibur.' 10
Moshav Zekenim #3 (in 16:1, citing Vayikra Rabah 20:8): It was for four matters - Kereivah (they entered the Kodesh ha'Kodoshim), they offered a Korban that they were not commanded, they brought strange fire, and they did not take counsel from each other.
Moshav Zekenim #4 (in 16:1, citing Vayikra Rabah 20:9): They sinned regarding four issues which are subject to Misah: 1. They entered after drinking wine; 2. They did not wash the hands and feet before entering; 3. They were Mechusar Begadim - because they were not wearing the Me'il. 11 4. R. Levi says that their eyes benefited from the radiance of the Shechinah at Har Sinai 12
Moshav Zekenim #5 (in 16:1): Because they entered the Kodesh ha'Kodoshim empty-handed (without Ketores) - "be'Korvasam Lifnei Hashem". 13
Targum Yonasan #2 and Sifra #1: They brought the Ketores with strange fire (fire taken from an oven ? Targum Yonasan) - which was Chulin and not from the Mizbe'ach ha'Olah.
Targum Yonasan #3: Refer to Sh'mos 24:11:2:6.
Sifra #2: Going back to Har Sinai ? when they saw Moshe and Aharon walking at the head of the people and they behind them, followed by the people, Nadav said to Avihu, 'It won't be long until these two old men die and we take over the leadership of the people'.
Ba'al ha'Turim: Refer to 10:2:2:1.
They ruled that, although fire would come down from Heaven, it was a Mitzvah to add human fire (Rashi). See also Torah Temimah, note 2, who elaborates. Seforno: They ruled that one should bring private Ketores in honor of the Shechinah. Refer to 10:1:1:5..
Which explains why the Torah follows this Parshah with the prohibition against drinking wine (See Pasuk 8, 9). Refer to 10:1:151:2 and note.
Others add that they also served with long hair and Mechusar Begadim (Oznayim la'Torah on 10:2).
Although Rashi does not actually state that Nadav and Avihu died for this reason, it is clear from his explanation there (in 16:1 & 2) that this is what he holds.
Rosh and Da'as Zekenim: This diminishes Hashem's honor, since people will say that human fire consumed the Korban., This is difficult however, for the previous Pasuk says "va'Tetzei Eish mi'Lifnei Hashem"!
Michtav me'Eliyahu (2, p.249, citing the Chafetz Chaim on the Sifra): They said so to prepare themselves to be ready for this great responsibility. Their sin was callousness - they should have said 'If, Heaven forbid they will die?' One opinion says that they merely thought so in their hearts!
And the Torah writes "be'Korvasam lifnei Hashem" as a hint that they said 'Let the day of their death come close.'
About which the Torah write in Ki Sissa Sh'mos, 28:35 "ve'Nishma Kolo? ve'Lo Yamus".
As the Torah write in Mishpatim Sh'mos, 24:11 "va'Yechezu es ha'Elokim".
That is why after mentioning their death, the Torah writes in Acharei-Mos, 16:3 "be'Zos Yavo Aharon el ha'Kapores, be Par ben Bakar ... ".
What is the meaning of "Asher Lo Tzivah osam"?
Da'as Zekenim: They were already forbidden - as the Torah writes in Ki Sissa Sh'mos, 30:9"Lo Sa'alu alav Eish Zarah", and Hashem did not command them [to do so in the form of a Hora'as Sha'ah].
Hadar Zekenim and Moshav Zekenim: We invert the Pasuk to read 'Asher Tzivah osam Lo Sakrivu'. 1
Hadar Zekenim: We similarly invert "va'Yeilech va'Ya'avod Elohim Acherim? Asher Lo Tzivisi" (in Shoftim Devarim, 17:3) as if it had written 'Asher Tzivisi Lo Sa'avodu.'
How could Tzadikim like Nadav and Avihu peform such a sin?
Moshav Zekenim (citing R. Yehudah ha'Chasid): They longed to see the radiance of the Shechinah and thought that through burning [Ketores] in the Heichal, they would be able to see it openly.
Vayikra Rabah (20:9) states that they were Mechusar Begadim, because they were not wearing the Me'il. But only a Kohen Gadol wears the Me'il?
Teshuvas ha'Rosh (13:21) #1: It says in Zevachim (102a) that they were considered Seganim (deputy Kohamim Gedolim), and the S'gan serves with the eight Begadim (Horiyos 12b). 1
Teshuvas ha'Rosh (13:21) #2: They considered themselves like Kohanim Gedolim, and accordingly they were lacking the Me'il.
Yedei Moshe (on Vayikra Rabah): The Ra'avad says that a Kohen is like a Kohen Gadol on the day he is anointed. 2
Yedei Moshe (on Vayikra Rabah, citing R. Naftoli Katz): Had they worn the Me'il, the angels would have departed and not killed them.
Rosh: However, some say that this is only if the S'gan once serve in place of the Kohen Gadol. Also, only Nadav was the S'gan (desinated to serve in place of Aharon, if needed). Rashi (102a) says that Elazar was the S'gan (after they died. Perhaps he holds that both Nadav and Avihu were Seganim in their lifetimes. - PF)
This implies that every Kohen must serve in the eight garments on the day he is anointed. If so, why in Tzav, 8:13 did Moshe dress Aharon's sons with only the four Begadim of a KOhen Hedyot? (PF)
QUESTIONS ON RASHI
Rashi writes that they were liable for drinking wine before entering the Mishkan.
Moshav Zekenim citing the Rosh, Riva (9:24): They were burned primarily due to Chet ha'Eigel 1 (refer to 10:12:1:1*). R. Chaim Paltiel (2) - or, they were liable from Matan Torah - "ve'El Atzilei B'nei Yisrael Lo Shalach Yado" (Sh'mos 24:11).
Ramban (on Pasuk 9) 2 and Moshav Zekenim: Drinking wine caused them to have wrong thoughts (Refer to 10:1:1:3).
Michtav me'Eliyahu (2, p.247): Even though they were not yet commanded, had they had proper fear of Hashem, they would not have entered after drinking even a Revi'is.
Moshav Zekenim: This explains why they were burned. One is not Chayav Sereifah for serving while drunk. R. Chaim Paltiel explains that also the Zekenim were Chayav Sereifah from Matan Torah; they were burned only after they sinned again - the Mis'onenim (in Beha'aloscha Bamidbar, 11:1).
Rashi writes that they were liable for ruling in front of their Rebbi, or drinking wine before entering the Mishkan. But the Torah writes in Bamidbar 3:4 "be'Hakrivam Eish Zarah"?
Moshav Zekenim #1: They should have brought coals from the outer Mizbe'ach, like it says in Tamid (5:5), but they brought fire from outside.
Moshav Zekenim #2: They should have brought coals - "ve'Lakach? Gachalei Eish" (Vayikra 16:12) refers to coals (Pesachim 75b), and they brought fire (a flame). However, we conclude there that also coals are called "Eish".
Moshav Zekenim #3 (citing R. Yishmael in Sifra): They brought Eish Zarah at the wrong time. Even though normally it is a Mitzvah to bring human fire, thaat day it was forbidden, in order not to diminish the honor of the fire above (refer to 10:1:1:5*). This is like Eliyahu 1 , who said "ve'Eish Lo Sasimu" (Melachim 1 18:25).
Refer to 10:1:1:4-6.
Eliyahu said so not for the honor of Hashem's fire, rather, to prove that the idolatry is impotent! (PF)
