Has time travel ever been discussed before in terms of Judaism? According to Judaism would (should) it be possible to travel through time?

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    @WAF hmm. What do you mean by that question? – yydl Aug 3 '11 at 16:42
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    Would your question be intelligible to a "traveler through time" or would the answer to such a person be "obviously yes" or "obviously no"? – WAF Aug 3 '11 at 16:53
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    ...but the real question is what happens when you time travel during sefirah? Do you celebrate Shavuot on a different day than everyone else? – Charles Koppelman Jul 18 '12 at 15:39
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    We are always traveling through time. – Daniel Apr 24 '13 at 4:49
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    It was discussed at length in Marvelous Middos Machine 3! – Y     e     z Jan 10 '18 at 19:20

In Menachot 29B, the following story is told (English taken from page 112 of here):

Rab Judah said in the name of Rab, When Moses ascended on high he found the Holy One, blessed be He, engaged in affixing coronets to the letters. Said Moses, ‘Lord of the Universe, Who stays Thy hand?’ He answered, ‘There will arise a man, at the end of many generations, Akiba b. Joseph by name, who will expound upon each tittle heaps and heaps of laws’.

‘Lord of the Universe’, said Moses; ‘permit me to see him’. He replied, ‘Turn thee round’. Moses went and sat down behind eight rows [and listened to the discourses upon the law]. Not being able to follow their arguments he was ill at ease, but when they came to a certain subject and the disciples said to the master ‘Whence do you know it?’ and the latter replied ‘It is a law given unto Moses at Sinai’ he was comforted.

Thereupon he returned to the Holy One, blessed be He, and said, ‘Lord of the Universe, Thou hast such a man and Thou givest the Torah by me!’ He replied, ‘Be silent, for such is My decree’. Then said Moses, ‘Lord of the Universe, Thou hast shown me his Torah, show me his reward’. ‘Turn thee round’, said He; and Moses turned round and saw them weighing out his flesh at the market-stalls. ‘Lord of the Universe’, cried Moses, ‘such Torah, and such a reward!’ He replied, ‘Be silent, for such is My decree’.

It could very easily be argued that the whole thing was a vision, but it does say that Moshe went and sat behind the 8th row and that he returned to G-d afterwards.


Shivchei HaBesht records an episode where the Baal Shem Tov wrote a letter to his brother-in-law R' Gershon of Kitov, telling him how he had been taken to task by the Heavenly Court for excommunicating a Torah scholar without sufficient cause. R' Gershon wrote back to say that this indeed had happened, but only after the date of the Baal Shem Tov's letter - in other words, he "time-traveled" and saw the incident before it occurred.

The Tzemach Tzedek of Lubavitch points out (Derech Mitzvosecha, Mitzvas Haamanas Elokus) that the Divine flow of energy to the world - both its spatial and temporal aspects - gets divided progressively finer during its "evolution" through the spiritual "worlds" leading down to our own. There is a level, he says, at which one moment contains ten to fifteen years' worth of events in our realm; it is this level, he says, that the Baal Shem Tov reached and thereby foresaw what was to happen.


Somewhat unconventional, but:

While commenting on a different point in the gemara (Chulin 91b), R' Yitzchok questions how Yaakov was "vayifga bamakom"- he chanced upon the place (Beis El/Yerushalayim) if the pasuk implied that he already reached Charan- vayelech Charana. R' Yitzchok answers that the land shrunk for him. Assuming space and time are interwoven, Yaakov would have traveled ahead in time as well.

The gemara continues the above by questioning why the Torah wrote "ki va hashemesh"- Yaakov lodged because the sun had set- implying that it set prior to its normal time. If not for the gemara's answer (that Hashem wanted the tzadik to lodge by Him and so made the sun set early so that Yaakov would be unable to depart), it's possible to say that for Yaakov, the sun set early because time bent for him along with the land.

Note: I have no clue if the math works out.


Time-travel into the past, according to Stephen Hawking's latest Scientific-Theory, is inherently a paradox. Paradoxes cannot exist in nature and as such, reverse-time-travel is physically impossible.

According to the Rambam, Hashem only does possilbe-miracles, where Hashem uses His direct-control of the physical world to perform natural-wonders. The Rambam addresses the classic question 'could Hashem create a square-triangle' (can God do anything impossible)? The Rambam's revelation is that Hashem can't make a square-triangle (he can't do something physically-impossible), but that's not a limit of Hashem's power, since He made the restrictions of our physical world. He said something along the lines of 'let the goyim have impossible-miricles, we'll have possible ones' (their miracles can't happen, ours can and do).

Accordingly, the Rambam would hold that reverse-time-travel, as a paradox of nature, would not be a miracle Hashem could perform.

Hawking's theory, that traveling to the past is a paradox and impossible, is also supported by a halacha from Talmud Bruchos, that it's assur to pray to change the past.

If you hear that there is a fire in your town, you shouldn't pray that it wasn't your house, it's too late if your house is on fire, and Hashem isn't going to go back and change it. instead you can pray that it won't spread to your house if it wasn't your house, or that they will be able to put it out quickly.

Also along those lines, expecting parents shouldn't pray that their baby be a certain sex after the first 40 days of pregnancy, since after 40 days the fetus already formed its sex-organs and Hashem's not going to go back and change it. (Berachot 60A)

Another quantum-halacha is once something observed, it can't be changed. (once it's seen it can't be un-seen)

I don't know where this halacha is from, but I was taught that you shouldn't count your money because, if you know how much money you have (you've observed it) then Hashem can't slip you more without your knowing (Hashem can't change it once you've observed it).

This would mean that since the past was observed by the people living in it, Hashem cannot send you back to change it.

Scientifically, observations effecting reality relate to Schrödinger's cat & Relational quantum mechanics.

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    I think the last concept is called "Blessing is only found in the hidden", I'm not sure where it's written. – chaimp Nov 24 '11 at 8:25
  • -1 Hawking's theories, as brilliant as they are, have no bearing on halacha. The concept that one ought not pray about past events has no connection to the feasibility of time travel. I don't have enough halachic source material on this for an answer, except to say that time is, in and of itself, a creation. If G-d wants to allow people to travel through time, nothing that Hawking or any other human being observes in the physical world can stop G-d from allowing it. – user1095 Jan 9 '12 at 17:23
  • @ will, One shouldn't pray to change past events because Hashem won't change the past. I think that's very connected to time-travel. -- While I agree that time is a creation, that doesn't mean that Hashem can do 'whatever he wants with it', at least according to the Rambam. A square cannot be a triangle, it's illogical, and Hashem can't make one in our physical world due to the restrictions that Hashem set. So if reverse-time-travel is also illogical, then according to the Rambam it would be impossible for Hashem to perform. – zaq Jan 9 '12 at 20:19
  • This doesn't address the first part of the question - has it been discussed? RaMBa"M was not discussing time travel (even though you are applying his comments that way). – Seth J Jul 18 '12 at 18:48
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    @chaimp It's in BM 42a. וא״ר יצחק אין הברכה מצוייה אלא בדבר הסמוי מן העין שנאמר יצו אתך את הברכה באסמיך תנא דבי רבי ישמעאל אין הברכה מצויה אלא בדבר שאין העין שולטת בו שנאמר יצו ה׳ אתך את הברכה באסמיך ת״ר וכו׳ מדד ואח״כ בירך הרי זה תפילת שוא הלפי שאין הברכה מצוייה לא בדבר השקול ולא בדבר המדוד ולא בדבר המנוי אלא בדבר שסמוי מן העין שנאמר יצו אתך את הברכה באסמך. רש״י: אין הברכה - שמתברך ורבה מאליו פויישו״ן בלע״ז: באסמיך - דריש ליה לשון סמוי מן העין: שאין העין שולטת בו - שנאמר באסמיך לשון גנזים – DonielF Oct 27 '16 at 18:56

When we talk about time travel, we must define what we mean.

If it mean that time is not a limitation ie. The affects of time, like old age, have no affect on the person then we have a Gemara in Taanis (23a) regarding Choni Ha’maagel, who slept for 70 years. And to him it was as if it was one day.

The Sefer Magen Avos (5:21) says that the time he was asleep, did not age him, despite that the world around him did age, as his former students and teachers had passed away.

The same Sefer mentioned above also says that when Moshe was on Har Sinai for 40 days and 40 days, without food or drink, he says because Moshe was unaffected by time, as if time has stopped for him.


I believe it was the Ibn Ezra that once said, the Past is Gone, the Future is not yet, the Present is but a mere second, so why worry? In Hebrew: העבר אין, העתיד עדיין, ההוה כהרף אין, דאגה מנין.

I think that the common concept of time travel is virtually impossible as it's non-existent. But... Hashem created time, which means he's above time, so to Him past present and future are one and the same, thereby he could have theoretically taken Moshe out of the realm of time and put him in R Akiva's Yeshiva.

The question here is though, did R Akiva see Moshe, could the people around him see him? Probably not as I believe a 20 foot tall with a shining face man would really stand out. So I agree with those that say it was a vision.

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    Welcome to MiYodeya Yossi. Since MY is different from other sites you might be used to, see here for a guide which might help understand the site. Note in particular the focus on sources. Since we don't know you, what you think is less useful than the sources you can bring to support your ideas. Note also that you say first "virtually impossible", then "non existent" then discuss TT. Contradictory no? You can edit if you wish. Welcome again and great to have you learn with us! – mbloch Sep 18 '18 at 7:32

There's a story in the Babylonian Talmud, Ta'anit 23a which tells of a Jewish scholar named Honi ha-M'agel who lived during the 1st-century BC.

In the Talmud, Rabbi Yohanan relates to Honi’s life being troubled by a verse in the Psalms (126:1) regarding “A Song of Ascents.” Honi wondered if it were possible to live seventy years in a dream.

The story goes that Honi was once journeying along a road where he saw an old man planting a Carob tree. Honi was eager to know the purpose of this tree. He approached the planter with his question. “How long does it takes for this tree to bear fruit?" The man replied: "Seventy years." This was because on average, it took nearly 70 years for it to grow. Honi nodded and asked him another question. “Are you certain that you will live another seventy years?" The man replied: "I found already grown carob trees in the world; as my forefathers planted those for me so I too plant these for my children." To this, Honi shrugged and sat down to have a meal. He must have wondered whether the man was foolish enough to think his children would live to see it ripe. Looking for shade, he planted himself next to the planter and rested, apparently for 70 years. When he awoke he found himself covered in rocks. Intent on finishing his journey, he walked a distance and sat next to an old tree where a man was picking fruit. Puzzled, He asked him if he were the same man who sowed the seed. the man replied no and that it was his grandfather who was responsible for this tree so that it will bear fruit and provide for further generations. To this, Honi pondered and said: "It is clear that I have slept for seventy years."

The point of the story is that others can still reap the rewards from your mitzvot if it's merited.

Taanit 23a Hebrew/Aramaic, Mechon-Mamre, Maharsha links the discrepancy of the Talmud and Josephus's account of Antiquities of the Jews, 14.2.1 21. It doesn't assume Honi was assassinated by Hyrcanus II but rather he fell into a deep sleep or a coma-state for the duration of 70 years.

We seem to have a Jewish Rip Van Winkle. Whether this supports the theory of time travel, I don't know. I tend to agree with Josephus's account and that this was a parable for the effects on others due to our good deeds

PS This story is usually associated with the holiday of Tu'Bishvat.


I'm with ZAQ - TT does not exist and can not exist according to Judaism.

  1. I know there are lots of stories of peeking (seeing) forward and backward in time, but this is not TT.

  2. There are no stories or even fantasies about physically moving a physical body in either direction and interacting with the environment.

  3. There are no parallel universes with any sort of interaction between them (there might be different Olamot, but they are unrelated one to another) because if they were relevant they were mentioned elsewhere.

  4. See Eliezer Ben Pedat's story (Taanit 25a) as G-d said to him: "To change anything I need to destroy the whole world and even then I'm not sure about your luck".

  5. I would say, that according to Judaism, the 4D world is one piece and just unfolds before our eyes. Just like a movie file on your disk that you watch one frame at a time, but it is all on your disk. So is the Creation in G-d's eyes.

  6. I brought additional proof in my other answer

NB. The famous saying "הפוך בה והפוך בה דכולי בה" is a sure bias in critical thinking that allows us to find firm evidence for just about anything in the Jewish tradition. We should be more careful about it and stop lying to ourselves.

  • Your “additional proof” I think is the main answer here. Most of the other stuff here is speculation, based on a preconceived notion that time travel is impossible. Take your first bullet point - you say “this is not time travel” but you don’t demonstrate why - almost like you’re saying “time travel is impossible therefore these stories can’t be interpreted as such.” A similar claim can be made against pretty much anything on this list (though I’ll give you that Gemara in Taanis). I didn’t give the downvote but I don’t disagree with it as it stands now. – DonielF Aug 26 '18 at 16:29
  • @DonielF Let's work it out one by one. #1 - Is seeing the future/past a TT? You might rightfully call it so, but I don't. (I'll number it for easy reference.) – Al Berko Aug 26 '18 at 16:36
  • I assume that you refer to, say, Menachos 29b referenced in an earlier answer. The wording of the story can be easily read (at least to me, and clearly to that poster) as saying that he actually sat in his class, not that it was a prophetic vision. I could see how that story could be read as such, but I find it much easier to read it as saying he actually was there. The story of the Ba’al Shem Tov, on the other hand, I could hear much more easily as saying it was Ruach HaKodesh, not time travel. – DonielF Aug 26 '18 at 16:43
  • #2 seems to be just an extension of #1: “Seeing the future isn’t time travel; therefore there are no stories about time travel.” – DonielF Aug 26 '18 at 16:46
  • As for #3... I assume you refer to multiverse jumping, which is another way of referring to the option of actually changing history. I’m not sure that that means they don’t exist so much as we have no evidence that they exist (a distinction which may apply to 1-2 as well). – DonielF Aug 26 '18 at 16:50

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