Dear friend, open your mouth wide and I will fill it with a major, albeit harsh, principle from the Torah of life: Since life on this earth is only a vestibule for the banquet hall which is the World-to-Come, only an instrument of G-d whose purpose is to bring man and the world to holiness and the yoke of G-d's kingdom, and since true life occurs only in the World-to-Come, the world of truth, it follows that in order to attain this goal and teach people fundamental lessons, G-d sometimes shortens peoples' lives.
Sometimes, those who pass away are righteous, innocent persons, even children and infants, and the fools and the “dead” who move around among us see in it only cruelty, or even lack of logic, direction and Divine conduct in the world. Life was given to man as a loan, a loan that he must pay off when the time comes, and that he is not entitled to refuse. As our sages said (Avot, end of Ch. 4): Perforce you were formed and perforce you were born; perforce you live, perforce you shall die, and perforce you have to give a strict account before the Supreme King of Kings, the Holy One, blessed be He. The two sons of R. Meir and his wife Beruriah died. Our sages describe how Beruriah acted before revealing the tragedy to her husband (Yalkut Shimoni, Mishlei 964): Beruriah set food before R. Meir. After he had eaten she said, “Master, I have a question to ask. Someone previously gave me a deposit to take care of for him. Now he has come to reclaim it. Should I return it or not?” R. Meir replied, “Daughter, if someone has a deposit, is he not obligated to return it to its owner?” She then said, “I would not return it without your knowledge.” Taking his hand, she brought him up to the bedroom. She pulled back the bed sheets and he saw his two sons lying there deceased. He began to cry and said, “My sons, my sons! My teachers, my teachers! My sons in proper behavior. My teachers in that they would enlighten me with their Torah.” At that moment she said, “Master, did you not tell me that we must return a deposit to its owner? 'The L-rd gave and the L-rd has taken away. Blessed be the name of the L-rd' (Job 1:21).”
Life is nothing but a deposit from G-d. It is decreed that one should live a specific length of time, and during that time he should fulfill the mission incumbent on him. Like anyone guarding a deposit, a person must guard his life, neither damaging nor making improper use of it. When the time comes, he must return it to its owner. Man's life on earth is exceedingly short; it passes in the blink of an eye. On the one hand, it is qualitatively of enormous importance, for only through it can a person fulfill the duty for which he was created. On the other hand, however, how brief and transient life is! It is compared to “the potsherd that breaks, the grass that withers, the flower that fades, the shadow that passes, the cloud that vanishes, the breeze that blows, the dust that floats, the dream that flies away” (U'Netaneh Tokef). Our true, eternal existence is in the World-to-Come, not here on earth. As our sages said (Avot 4:16), “This world is like a vestibule before the World-to-Come. Prepare yourself in the vestibule so that you may enter the banquet hall.” This carries both encouragement and a warning, and we must assimilate the whole message with pure acceptance of the yoke of Heaven. A person must understand his mission on earth and the idea that life was given only to fulfill that mission. He must understand how brief and transient life is and how much emptiness pervades it. Once he understands these things, he will recognize that he need not fear either the day or moment of death as long as he pursues life by accepting the yoke of Heaven and being constantly ready to sanctify G-d's name through self-sacrifice. If someone has attained immortality by doing G-d's will, what does he lose if he suddenly leaves this world? One should not delude oneself into viewing longevity as an end in itself. The main thing is life's quality: how a person lives. Does he attain true life as defined by G-d? When a person exists on this earth without accepting the yoke of Heaven and without readiness to sacrifice his life to sanctify G-d's name, that is not “life” at all, but a bestial existence.
By contrast, if someone's life was cut off in its prime through his sacrificing himself, that person was alive before, he is still alive now, and he will remain alive forever in the World-to-Come. The wise person who understands G-d's ways and Torah will thus never fear. He will always be ready to sacrifice his life to sanctify G-d's name, and precisely in this way, to continue living. When G-d wishes to demonstrate how great, awesome and just He is, He shows no favoritism even to the righteous. He killed the two sons of Aaron, Nadab and Abihu, who were righteous (and not only did He kill them, but He took their souls on the most joyous and holy day, that of the Tabernacle's dedication). What great suffering was caused to Aaron, their father, and Elisheva, their mother! Dear reader, let us consider our grave duty to fear G-d. As explained above, G-d will sometimes take a person before his time to teach a profound idea that will sanctify His name. G-d's doing so involves no cruelty whatsoever. On the one hand, life on this earth is short and fleeting. It is not eternal. If someone dies young, as much as a tragedy it is for his relatives and friends, he is really only leaving this earth a few years before he would have anyway. On the other hand, someone whom G-d kills to teach that person's nation and contemporaries and the world a Divine lesson that will sanctify G-d's name, thereby ascends to greatness. Our sages said (Vayikra Rabbah 2:1), “Ten things are called precious... From whence do we know that the death of the saintly is among them? It says, 'Precious in the sight of the L-rd is the death of His saints' (Ps. 116:5).” Thus, those saints who die to sanctify G-d's name are precious, and their death is precious.
G-d suffered greatly for having killed Nadab and Abihu, who were righteous. As our sages said (Bamidbar Rabbah 2:23): “Nadab and Abihu died before the L-rd” (Num. 3:4): The Torah's mentioning their death in several places teaches that G-d was sorrowful because Aaron's sons were dear to Him. Likewise it says, “I will be sanctified through those close to Me (Lev. 10:3). Vayikra Rabbah (20:10) says, “The death of Nadab and Abihu was twice as hard on G-d as it was on their father.” R. Eliezer HaModai says (Sifri, Pinchas 137): Consider how dear the righteous are before G-d. Wherever it mentions their death it mentions the sin that led to it as well. Why does it go to such lengths? To avoid giving mankind the pretext to say that righteous men died because they had acted corruptly in secret. Thus, in four places it mentions the death of Aaron's sons, and in each it mentions their sin to make known that they had no sin but this. One should be aware that in all four places where G-d mentions Nadab and Abihu's sin, He points to the strange fire that they brought in the Holy of Holies. This was their sin, as noted in previous sources. When they saw the fire descend, they became excited and followed their own Halachah that it was a mitzvah to bring regular fire as well. They wished to stress the connection between G-d's holiness and that of man. At the root of all this was their desire to enter the Holy of Holies, to commune there with G-d, and to offer an incense that would be accepted. Although Nadab and Abihu were righteous and wished to come close to G-d, the outcome of their deed was the diminishing of G-d's glory and of Israel's reverence for Him. Hence G-d made Nadab and Abihu an eternal example, an everlasting reminder of the crucial principle that we must demonstrate fear of G-d through reverence for the Temple: This is what G-d meant when He said, 'I will be sanctified through those close to Me, and thus glorified before all the people.' Aaron remained silent (Lev. 10:3).
Besides the general reverence all are obligated to feel, there are concrete limitations on a persons' entering the Temple, depending on who he is. If he is and Israelite, his being pure or impure has a bearing, as does the type of impurity, itself. If he is and ordinary Kohen, his being physically blemished, not cutting his hair or wearing torn clothes has a bearing. If he is the Kohen Gadol, he faces other limitations when he enters the Holy of Holies once each year. Although the reason for these limitations is the levels of holiness within these boundaries, entering in opposition to that holiness indicates a lack of fear of G-d, the levels of holiness having been fixed chiefly so man would experience that fear. What emerges from all this is that G-d gave us life to perform a specific task, and created man to fulfill that task and bring the world holiness, purity, humility, fear of Heaven and acceptance of G-d's yoke. This being the case, when the times demand it, G-d might also remove someone from this earth to teach a specific idea. We need not mourn such a person. Rather we must stand silently as did Aaron and accept sentence. We must transcend our natural sorrow and be joyful about this exalted soul. G-d's holy ones are likewise adored and lauded through this, for by their early deaths they complete their role on this wretched earth in holiness and acceptance of the yoke of Heaven, and there is nothing greater than that. No exit from this earth could be more exalted.