Is there any profound explanation why God created sleep for humans? Are there animals that don't sleep and rest by shutting down one hemisphere of the brain at a time, because that mechanism wouldn't be appropriate for us? There is also the question of the danger that sleep provides, something or someone can harm you when you are unconscious. People sleep for 1/3 of their lives, wouldn't that 1/3 be better used with some activity? In other words, aren't we throwing away 1/3 of life in exchange for certain benefits like purifying the subconscious or restoring the body?

  • You're assuming that our lives would be equally long if we were hypothetically created without the need to sleep.
    – shmosel
    Mar 13, 2023 at 0:14
  • No. I'm not ignoring the scientific discoveries regarding the need for sleep, but as I mentioned, there are animals that don't sleep like us and live normally. The question I posed at the end was more the utilitarian aspect in a theological connection than a scientific one, what is the good explanation for the existence of sleep, if there is such an explanation?
    – Thales
    Mar 13, 2023 at 0:31
  • 2
    I'm saying if G-d had created us without a need for sleep, He might have given us shorter lifespans with the same overall quantity of "productive" time. So it's valid to ask why we sleep, but asking why the time isn't better spent is speculating about counterfactuals.
    – shmosel
    Mar 13, 2023 at 0:50
  • Sleep by science has a function, repair the body and mind. What I question is theologically, does spending 1/3 of life justify this aspect? Or does Judaism have something deeper to say about sleep that science has so far missed? For example, God created woman for man to satisfy the aspect of loneliness, sleep must have something deep that maybe we don't know or can't know beyond the scientific question. I'm just conjecturing if there's a greater explanation for why it exists.
    – Thales
    Mar 13, 2023 at 1:07
  • We certianly are not throwing away 1/3 of life in exchange for certain benefits such as restoring the body. When you sleep your body repairs itself. That is a good trade-off.
    – Turk Hill
    Mar 13, 2023 at 4:42

6 Answers 6


I don't know the source, but remember learning in class, that the reason G-d created us needing sleep was that so we can start the new day with a clean slate.

It is much easier to decide to make a change when you have a break after the previous day. If all the days would blend together with no break, it would be much tougher to decide to act differently. There is an old saying, "Tomorrow will be completely different". Sleep makes that possible.

If anyone knows the source, let me know. Sounds like something that would be found in a Mussar Sefer.


There have been some great answers given so far. I would like to suggest another answer, I heard this answer on the Radio shows of Rabbi Mordechai Weinberger LCSW which I think is also based on the Rambam (book 3 chapters 10). The way Hashem made the world is dialectic, in order to understand sight we have to be able to blind ourselves. There is something, there is nothing. Each thing in the world needs an opposite in order to keep the world balanced.
One of the reasons this could be is as humans to understand we are “just a man” we will never be able to achieve or understand the ways of Hashem, as we are finite. We need dialectics to keep us alive. Sleep is a human need in order to keep us functional as a finite human. Otherwise the awake would not be awake.
Hashem created night as a way for us to show our powerlessness and show how the dialectic of us sleeping and letting Hashem be in control, helps us. I have spoken to many people who have told me their issues with sleeping at night is because (anxiety) they don’t feel they can relinquish control. Often blaming it on bitachon and Emunah.


Rav Avigdor Miller was asked your question as well and explained (TAPE # 598):

Hakodosh Boruch Hu made this world for the purpose of recognizing Him. Now, how can people recognize Hashem when they’re so busy in this world? You’re thinking only of your own affairs and you forget about Hashem. So Hashem says, “I’m going to remind you of Me.” And so, you get hungry. You have to eat, you need food, and then when you get a piece of bread: “Oh, I thank You Hashem, what would I do without the bread?! I can’t live without bread.” And the bread causes you to be grateful, to love Hashem, and you're fulfilling your purpose in the world.

Let’s say, a person is tired; he's very tired, and his body gets worn out. And now he needs sleep to feel rested. Are you going to just sleep like a cat sleeps? So Hashem says, no. If you’re able to go to sleep, you have to thank Hashem for that. Some people can’t sleep; some people are sick and they can’t sleep. Sleep is a blessing and you have to thank Hashem for the sleep. That’s why He makes you tired. Say it with your mouth: "Ah geshmakeh pleasant night’s sleep!" It’s better than eating the most delicious things! In the morning you get up, and you’re refreshed, you’re a new person. מודה אני לפניך - "I thank You, Hashem." So the sleep is the for purpose of causing people to be more grateful to Hashem.

That’s only one of the benefits of sleep. There are other benefits too, but this is one of the benefits of sleep that is included in the great program of making people more perfect in this world.


Whenever we are asked for a "profound reason" for something, the most profound we can go is to ask, what are we emulating in Hashem visávis that thing?

I've heard it in chassidus like this. Why did Hashem create the world? He was yachid, He was perfect, He was eternal. Why ruin that?

Why do we wake up in the morning from sleep? It is bliss that could last forever, it is problem free, it is comfortable and perfect. Why ruin that?

For Hashem, and for us, it's the same answer: because we want something.

That's the only reason we get out of bed, and that's why Hashem created the world. There is a desire to fulfil that is greater than the sleep, and that the sleep isn't going to accomplish.

Once a day, Hashem wants us to remember this concept, feel it in our bones. As NJM wrote in their answer via Rav Miller A'H, sleep is more pleasurable than food, ranking it very high in the list of human pleasures. And yet, we realise that purpose, meaning, and the pursuit of what is important are worth far more than remaining in a state of perfect bliss. We, l'havdil, emulate Hashem every day when we wake up and immediately connect to Him by saying Modeh Ani, like He does continually every moment; creates the world and seeks us; a Godly impulse, so to speak, that we are to study and understand, for His sake, as the Torah commands:

ושננתם לבניך ודברת בם בשבתך בביתך ובלכתך בדרך ובשכבך ובקומך

teach them [the words of Torah] to your children and discuss them, when you sit at home, and when you journey on the road, and when you go to sleep, and when you rise.

  • Consider all the opportunities for kindness and mitzva unique to sleep. The closeness one has with ones children at bed time, with ones spouse, the opportunities to give someone a shelter and a bed, to make it comfortable for them, even one's servant! To let someone sleep and not interrupt, the opportunity to use sleep as a means to serve Hashem and others etc.
    – Rabbi Kaii
    Mar 13, 2023 at 14:05

I heard that it’s a way for Gd to humble humans. If we think we’re so powerful and can be like Gd, Gd comes along and limits us and makes us dependent on sleep, shutting us down for a third of the day

  • Perfect, it is already something deeper than simply restoring us, this is a scientific and even evolutionary explanation, something that Judaism does not support.
    – Thales
    Mar 13, 2023 at 13:35

Upon Hashem’s completion of the world, the Torah writes how G-d observed His creation and commented:

"והנה טוב מאד"

“And behold it was very good” (Bereishis 1:31)

Ramban (on Devarim 6:13) brings a Midrash that explains that this term “very good” is a reference to sleep, which helps to invigorate a person and thereby ensure one can more readily apply themselves to Torah learning as well as all their physical requirements.

“And G-d saw every thing that He had made, and, behold, it was very good — this refers to sleep. Is sleep good? [It is ‘good’] because, if a person sleeps a little, he rises and engages in the study of Torah.”

In a similar vein, Rambam (Hilchos De'os 3:3) asserts:

"אם ישן לדעת כדי שתנוח דעתו עליו וינוח גופו כדי שלא יחלה ולא יוכל לעבד את ה' והוא חולה, נמצאת שנה שלו עבודה למקום ברוך הוא."

“If a person sleeps in order to allow his mind to rest and to give rest to his body so that he should not become sick and unable to serve G-d because of illness, in this case his very sleep is service of G-d. This is the meaning of the precept of the sages that 'all your deeds should be for the sake of heaven'”

Refer also to Pirkei D'Rebbi Eliezer 12:

מה עשה הב"ה ברא שנת חיים ואדם שוכב וישן והוא מזונו ורפואתו וחיים לו ומנוח לו, שנ' ישנתי אז ינוח לי

What did the Holy One, blessed be He, do? He created the sleep of life, so that man lies down and sleeps whilst He sustains him and heals him and (gives) him life and repose, as it is said, "I should have slept: then had I been at rest" (Job 3:13)

  • Thanks for the wonderful, diverse sources as always Dov. In this case I question if any of them address the OP's question? They are asking for a profound reason for the need for sleep, and as far as I can tell all of these answers presume that sleep is already needed (even though the Ramban isn't using it that way in his question, his answer turns out like that it seems!) and what do we do to make it into a Divine service. Is that therefore your answer? Just another aspect of life to make into a Divine service? Is that profound, given as it's an answer that applies to every aspect of life?
    – Rabbi Kaii
    Mar 13, 2023 at 13:18
  • @RabbiKaii I heard it from somewhere, that when we sleep our soul or spirit rises to the presence of God and there we have a dialogue with Him. Is this grounded?
    – Thales
    Mar 13, 2023 at 13:34
  • @Thales yes, see Derech Hashem 3:1:6
    – Rabbi Kaii
    Mar 13, 2023 at 13:38
  • @RabbiKaii - I would argue being able to serve G-d at the requisite level is pretty profound...
    – Dov
    Mar 13, 2023 at 16:37
  • @Dov the klal of being able to turn every aspect of life into Divine service is intensely profound, shkoyach for recognising this! What, b'phrat in sleep is profound?
    – Rabbi Kaii
    Mar 13, 2023 at 16:40

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .