(31) Moses said to Aaron and his sons: Boil the flesh at the entrance of the Tent of Meeting and eat it there with the bread that is in the basket of ordination—as I commanded: Aaron and his sons shall eat it; (32) and what is left over of the flesh and the bread you shall consume in fire. (33) You shall not go outside the entrance of the Tent of Meeting for seven days, until the day that your period of ordination is completed. For your ordination will require seven days. (34) Everything done today, the Eternal has commanded to be done [seven days], to make expiation for you. (35) You shall remain at the entrance of the Tent of Meeting day and night for seven days, keeping the Eternal’s charge—that you may not die—for so I have been commanded. (36) And Aaron and his sons did all the things that the Eternal had commanded through Moses.
Ibn Ezra on Lev. 6:33:
Some explain this to mean that they could not go out during any of the seven days, but that they could go out at night to take care of their bodily needs. In my opinion, they could go out for this purpose, whether it was day or night. A great scholar has suggested that they dug a trench for this purpose in the courtyard of the Tent, but this is farfetched. One must not overinterpret the text. We are told that "the Israelites bewailed Moses in the steppes of Moab for thirty days" (Deut. 34:8) as if there was not a single moment during the thirty days when they were not crying. Our verse simply means that Aaron and his sons stayed at the entrance of the Tent of Meeting day and night, not occupying themselves with any other task or going to some other location.
Nachmanides on Lev. 6:35:
According to the Sifra, the point of this verse is that they should not leave the Tent of Meeting, day or night, during the hours of service - that is, until they had finished all of the service required of them at a particular time. This rule that priests should not drop what they are doing and leave is, of course, operative throughout the generations. It is a capital offence.
Abarbanel on Lev. 6:35:
He may have been hinting to them here that leaving the sacred enclosure to bring fire from outside it would entail death, as was indeed about to happen to Nadab and Abihu.
(1) Now Aaron’s sons Nadab and Abihu each took his fire pan, put fire in it, and laid incense on it; and they offered before the Eternal alien fire, which God had not enjoined upon them. (2) And fire came forth from the Eternal and consumed them; thus they died at the instance of the Eternal.
(א) ופתח אהל מועד תשבו יומם ולילה שבעת ימים. הזהירם שלא יצאו מפתח אהל מועד יומם ולילה בשעת עבודה, כלומר עד שישלימו כל העבודה המוטלת עליהם באותו העת, והיא מצוה נוהגת לדורות שלא יניח כהן עבודה ויצא וזהו שאמר בכהן גדול (ויקרא כא) ומן המקדש לא יצא ולא יחלל, אימתי אינו יוצא ואינו מחלל הוי אומר בשעת עבודה, ואם עשה כן חייב מיתה, שנאמר פן תמותו, ומכלל לאו אתה שומע הן. (ב) ומה שהזהירם שלא יצאו מן הפתח לא ביום ולא בלילה, כוונת הפסוק בשעות הראויות לישב שם, שהרי בשר ודם הוא מוכרח לעשות הענינים הגופניים, כיוצא בו אמר הכתוב בבנין ביהמ"ק (מלכים א ו׳:ל״ח) ויבנהו שבע שנים, ואת ביתו בנה שלמה י"ג שנה, שאין לכלול בהם השבתות והמועדים, כי הכוונה בימים הראויים למלאכה, אף כאן הזהירם שלא יצאו מן הפתח בשעות הראויות לישב שם. (ג) ובמדרש ופתח אהל מועד תשבו יומם ולילה אלו שבעה ימים אבלות של נדב ואביהוא, שהרי הקב"ה שמר על עולמו תחילה. באורו שהתאבל שבעה ימים על העולם שעתיד ליחרב בדור המבול, שנאמר (בראשית ז) ויהי לשבעת הימים ומי המבול היו על הארץ. ואמרו שם ומתאבלין על המת קודם שימות, אלא אדם שאינו יודע מה שעתיד להיות אינו מתאבל עד שימות המת אבל הקב"ה שיודע מה שעתיד להיות שמר על עולמו תחלה, אף כאן אמר הקב"ה ופתח אהל מועד תשבו יומם ולילה שבעת ימים, שמרו על אחיכם שבעה כדרך ששמרתי אני את עולמי שבעה, וזהו שכתוב ושמרתם את משמרת ה'.
(1) ופתח אהל מועד תשבו יומם ולילה שבעת ימים, “and at the entrance of the Tent of Meeting you shall dwell for seven days.”
(3) A Midrashic approach based on (Tanchuma Shemini 1): when the Torah speaks of “and you shall remain at the entrance of the Tent of Meeting day and night,” this is a reference to the seven days of mourning for the deaths of Nadav and Avihu. While it is true that at that point in time these two sons of Aaron had not died as yet, we know that God Godself observed seven days of mourning for an event which had not yet occurred. This was the reason that the Torah wrote in Genesis 7,10: “it was after the seven days, and the waters of the deluge came upon the earth.” God had observed seven days of mourning over the necessity that God had to destroy so much of God's own handiwork. In connection with that verse, the sages asked: “can one then mourn someone before he died?” If such a thing is not possible or not appropriate why did G’d mourn the event before it happened?” Humans who do not know what is in store in the future cannot mourn an event which has not yet occurred. God who does know, is able to do so. In our instance, God told Aaron and his sons to observe seven days of a special nature although they were not aware of the reason. God wanted them to act as God had acted prior to the deluge. This is why the Torah wrote the words 'ושמרתם את משמרת ה, “you shall observe the observance observed by the Lord.” [If I understand this Midrash correctly, Nadav and Avihu sat in mourning of their own deaths prior to it having occurred. It would prove that Nadav and Avihu’s death had already been decreed prior to their taking “alien fire” into the Sanctuary, i.e. something unbidden, that this was only the occasion which determined when G’d’s decree would be carried out. Ed.]
Rabbi Steven Exler, "Challenging Isolation"
Nahmanides points out astutely that Aaron’s sons did not merely follow God’s word — they added something of their own. Perhaps it is in their very addition to the command for isolation that Nadav and Avihu get carried away and offer this strange fire. God commands them to separate for seven days to prepare for the consecration of the Tabernacle. In their detachment they lose sight of their role to lead the community and instead offer up their own fire.
This fire is brought on the eighth day. Was it this extra day of isolation that pushes Nadav and Avihu over the edge? The Sages support this idea, suggesting that Nadav and Avihu never married and did not have children. In the Sages’ world, marriage and child-rearing were moorings to anchor one to the community. We now see the irony in sharp relief: the isolation that was meant to be their very protection from death becomes, so painfully, their downfall.
The story of Nadav and Avihu teaches us that isolation should be treated as a means to accomplishing a goal, not an end unto itself, and that isolation is never meant to be a permanent state.
[Rabbi Shimon bar Yohai and his son Rabbi Elazar] went and they hid in a cave. A miracle occurred and a carob tree was created for them as well as a spring of water. They would remove their clothes and sit covered in sand up to their necks. They would study Torah all day in that manner. At the time of prayer, they would dress, cover themselves, and pray, and they would again remove their clothes afterward so that they would not become tattered. They sat in the cave for twelve years. Elijah the Prophet came and stood at the entrance to the cave and said: Who will inform bar Yoḥai that the emperor died and his decree has been abrogated?
They emerged from the cave, and saw people who were plowing and sowing. Rabbi Shimon bar Yoḥai said: These people abandon eternal life of Torah study and engage in temporal life for their own sustenance. The Gemara relates that every place that Rabbi Shimon and his son Rabbi Elazar directed their eyes was immediately burned. A Divine Voice emerged and said to them: Did you emerge from the cave in order to destroy My world? Return to your cave.
They again went and sat there for twelve months. They said: The judgment of the wicked in Gehenna lasts for twelve months. Surely their sin was atoned in that time. A Divine Voice emerged and said to them: Emerge from your cave. They emerged. Everywhere that Rabbi Elazar would strike, Rabbi Shimon would heal. Rabbi Shimon said to Rabbi Elazar: My son, you and I suffice for the entire world, as the two of us are engaged in the proper study of Torah.
As the sun was setting on Shabbat eve, they saw an elderly man who was holding two bundles of myrtle branches and running at twilight. They said to him: Why do you have these? He said to them: In honor of Shabbat. They said to him: And let one suffice. He answered them: One is corresponding to: “Remember the Shabbat day, to keep it holy” (Exodus 20:8), and one is corresponding to: “Observe the Shabbat day, to keep it holy” (Deuteronomy 5:12). Rabbi Shimon said to his son: See how beloved the mitzvot are to Israel. Their minds were put at ease.