Many have the custom to stay up late on Shavuot night and read the Tikkun Leil Shavuot, selections from the entire Torah, including the Five Books of Moses, the Prophets and Writings, Mishnah, Talmud, Zohar, and so on. Some people do not recite the Tikkun but simply study the entire night, until morning.

What is the reason for this custom that we stay up very late on Shavuot, or don’t sleep at all? The Midrash states that the night before the Giving of the Torah, the Jewish people went to sleep. Why did they go to sleep the night before getting the Torah? “Because sleeping on Shavuot night is sweet, and the night is short!” The Midrash goes on to say that during that night a miracle occurred and mosquitoes did not bite them.

I don’t know where you live, but where I live, in Kfar Chabad, we have a mosquito plague, and very often you wake up in the middle of the night — eeeee… You try and find that mosquito that’s not letting you sleep. This can go on for hours. But that night, the mosquitoes didn’t bother anybody. It was a very sweet and peaceful sleep.

When G‑d came in the morning to give them the Torah, the Midrash continues, they were still sleeping. G‑d says, “I came and there was no one; I called and there was no answer.” G‑d is ready to give them this great gift and everybody’s asleep. G‑d has to wake them up and he says, "Nu, it’s time to get the Torah."

This is what the Midrash states. But what does it mean? There’s obviously more to it than meets the eye. The Rebbe points out that the Torah is always very, very careful about not saying a bad word. In other words, the Torah in general is very clear to do things in a positive way. When the Torah says something negative, such as calling an animal spiritually impure (tameh), this is only for the purpose of practical instruction. Where no practical instruction is intended, the Torah will go out of its way to use positive words.

The Torah describes impure animals as those “which are not pure,” rather than as impure. But when it comes to matters pertaining to Kosher, when one has to know the law clearly, the Torah does use negative expressions. Normally, negative words do not have to cross your lips; use a euphemism, unless you have a specific reason to be blunt and explicit. For example, there is a very serious disease, a malignant disease, that one shouldn’t call by its name, for that adds to its power. Or when you’re talking about certain parts of life that are very intimate, you can talk about them in a way that people know what you mean, without being explicit.

Accordingly, why does the Midrash speak so disparagingly about the Jews before the receiving of the Torah? Let’s say they didn’t do such a good thing — is there any reason to publicize it so that all future generations will know how bad they were, that instead of waiting up eagerly for the Torah they went to sleep? That’s not such a nice thing to say. The Torah could have overlooked it. What kind of teaching is it for us to know that our forefathers did something that isn’t so great? After all, ever since then we’re doing a Tikkun for it, we’re trying to repair it, which means that it wasn’t a good thing. So let’s just say simply that they overslept a little, and we say Tikkun. But the Midrash goes into great detail.

Our sages go into all of the details for there are several lessons that can be learnt.

It just doesn’t make sense that they went to sleep and overslept on that night, because we know that from the very day they came out of Egypt they started counting the days until Sinai. They started counting because of the excitement of looking forward to the Torah. It was a natural when one wants something one counts the days until it arrives. Our sages say that during each day of the seven weeks of the counting, the Jews in the desert, rose to a higher spiritual level. So you can imagine that by the time they reached the 49th day of counting and the 49th level of holiness, they were on a much higher level than they were the day they began the counting. On the night before they received the Torah, having reached a higher level of understanding and sensitivity — precisely now they went to sleep, and overslept?! It just doesn’t make sense.

The Chassidic masters explain that G‑d gave us a soul and he clothed the soul in a body. We are fully aware of the fact that our body is what we see and experience. When the soul leaves the body, the body remains a corpse, like a doll; there’s nothing there. The body is essentially subservient to the soul. Now, even though there’s a great purpose in living in this world in a body, for if there wasn’t, G‑d would not have created a world and would not have put us in the world, nevertheless, it is clear that the soul is in a sense confined within the body. There is a certain restraint that the soul must undergo because it is in a body. If the soul was not in a body it wouldn’t have to stop serving G‑d in order to eat and sleep and wash the dishes. There are certain needs that the body has that put a damper on what the soul would want to do twenty-four hours a day. So the body, in a sense, prevents the soul from expressing itself fully, and from serving G‑d constantly. A person gets tired. A soul doesn’t get tired. After a while you get bored. You lose your train of thought. You can’t concentrate any more. You need to sleep, you need to rest, you need to have your coffee. We’re just human beings. So the body slows the soul down.

However, when a person sleeps, a totally different thing happens. During the time of sleep, even though the person is obviously still alive, the heart still beats and the person still breathes, nevertheless, a segment of the soul leaves the body during the time of sleep.

During sleep there is a loss of consciousness. One does not fully hear, nor speak, nor see. There is an idea of death, a whisper of death — the Talmud calls sleep one sixtieth of death. Many people die in their sleep. Because during sleep everything slows down. The heart, the respiration, everything functions at a much slower pace than when the person is awake. During sleep the soul that was inside the body rises to its source above.

During sleep, when the soul is free of the body, it can in a sense go higher and reach revelations that cannot happen during the day, when a person is awake. At Sinai, this was the intention of the Jews in going to sleep. They knew that they had been working for seven weeks to elevate themselves to be ready to receive the Torah. But all of their preparations had been done, in a sense, during the day when they were awake and conscious. And they felt that now that they had reached such a high level, maybe now, if we go to sleep, our souls will reach such a high level that we can get the Torah while asleep. For we will be on a much higher level than we can attain through our own efforts. This was the true intention. They were hoping that through their sleep they would be able to reach a level of holiness that would be much greater than they could reach on their own accord during the day.

This is what the Midrash explains: Their sleep on Shavuot night was very sweet. Sleep can only be great and holy and special if you are on the level of Shavuot, if you have done all the necessary preparations. Then you can go to sleep with the hope that great things will happen, that you will see great revelations during your sleep.

“The night was short.” Here “night” alludes to concealment. We know that darkness, night, hides things. Have you ever tried looking for your glasses in the middle of the night and then in the morning, there they are just by your night table, two inches away from your hand? At night you just grope and you can’t find your slippers or anything. So what does the night do? The night doesn’t change anything. It just hides things. You cannot see. In the day you see it all, it’s so simple.

The Jews had reached a level where the concealment was minimal. They had almost overcome most of the night. There was still a bit of a night left but it was much shorter than it was when they started. So they felt, now we have done what we can do with daytime, let’s see what sleeping can do for us.

G‑d, in recognition of their good intentions said, “You know what? They’re really so sincere that I will help them along by preventing the mosquitoes from biting.” Had G‑d been opposed to their sleeping He wouldn’t have made this tremendous miracle that the mosquitoes which bit last night and the next night, all of a sudden this night didn’t bite.

Why, then, do we recite the Tikkun year after year? Because G‑d says, “I know what your idea was, but you made a little mistake. That’s all. It was an innocent error. I’m not punishing.” We don’t see that there was any punishment. We don’t see in the Midrash or in the Torah that there was ever any reprimand or any punishment meted out to them. The only thing G‑d said is, “I want you to make a Tikkun. Don’t do it again, and to remember that you shouldn’t do it again, every year I want you to stay up.”

What was their mistake? It was a very innocent error that many people still make today — that the ultimate purpose is the spiritual world, rather than the physical world. G‑d , however, wanted a dwelling place in the lowest world, as the Midrash states. Actually, to make a dwelling place for G‑d in this world was not possible until we received the Torah, and G‑d annulled the decree separating spirituality and physicality, so that now even the physical can become spiritual through the service of Jews. Thus, their error was entirely understandable, for it took place before the Torah was given.