Can one go back in time in order to complete a minyan, when his past self is already one of the minyan men?

On one hand, the requirement for ten men is met.
On the other, two of these men are actually the same man (albeit from different times).

This question is Purim Torah and is not intended to be taken completely seriously. See the Purim Torah policy.

  • 1
    Welcome to Mi Yodeya Yehuda!
    – mevaqesh
    Commented Feb 27, 2017 at 16:13
  • 5
    Reminds me of the question of whether a woman can light one candle in front of a mirror instead of two. Commented Feb 27, 2017 at 16:20
  • 1
    Is this actually Purim Torah? ;) meta.judaism.stackexchange.com/questions/3743/…
    – DonielF
    Commented Feb 27, 2017 at 19:05
  • 1
    As soon as I saw this in sidebar I knew Purim approached.
    – Joshua
    Commented Feb 28, 2017 at 3:32
  • 2
    Can you say kaddish for your deceased father if you go back to a time when he was alive and he is part of your minyan?
    – Nic
    Commented Mar 1, 2017 at 16:28

5 Answers 5


Rav Natrunai Gaon appears to address this. He writes:

תשובות רב נטרונאי גאון - ברודי (אופק) אורח חיים סימן קכט

ואף על פי שעובר זמן, תפילה

Even if one travels through time, [his prayer] is considered a [valid] prayer. (Translation my own).

The implication is that a time traveler's prayer is legitimate in all respects, including inclusion in the minyan.

This is stated more clearly in later sources such as the Mishnah Berurah (70:23):

אפילו יעבור זמן תפלה בצבור

Even if he travels through time, [his prayer is considered] tefillah betsibbur. (Trans. my own).

Note that although it could be argued that Rav Natrunai is not referring to a time traveler double counting himself in a minyan, but rather simply making up a missed prayer, the Mishnah Berurah who speaks of tefillah betsibur evidently understands Rav Natrunai as indeed referring to our case of the time traveling double counting minyan man. (For if he weren't double counting himself, why would his tefillah betsibbur be an different from anyone else's?).

  • 1
    But is it valid more than once for the same service? Aren't we concerned about b'rachot levateila? He's obligated for (say) mincha once, not twice or more. Commented Feb 27, 2017 at 20:49
  • Of course! Otherwise what is Rav natrunais hiddush?
    – mevaqesh
    Commented Feb 27, 2017 at 21:03
  • I assume that Rav Natrunai's chiddush is that your prayer is valid even though you missed its proper time the first time around. Overslept last Tuesday and well past the make-up time? No problem -- go fix it! But that doesn't mean you can do it twice. Commented Feb 28, 2017 at 3:33
  • @MonicaCellio Interesting. That is certainly a novel alternative interpretation. If all I had was Rav Natrunai, I might agree. However, the MB's extension to tefillah betsibbur seems to only make sense if the time traveler is double counting himself at the minyan. Because once we accept the basic hiddush (that you are proposing R. Natrunai intended) that the time traveler may pray even if he missed it the first time, it seems obvious that he would also reap the benefits of tefillah betsibur. If he can pray, and he has a tsibbur, why wouldnt it be tefillah betsibbur. [cont.]
    – mevaqesh
    Commented Feb 28, 2017 at 3:45
  • [cont.] therefore, the MB's discussion of tefillah betsibbur must refer to a case in which the time traveler is double counting himself in the minyan as in my interpretation of Rav Natrunai.
    – mevaqesh
    Commented Feb 28, 2017 at 3:46

There are an infinite number of universes in which meeting yourself causes at least one if not both to cancel out. Thus going back in time to when you are already there is a form of suicide and prohibited. In fact, in those in which both are canceled, you will be removing one of the people already there.

  • " there is a form of suicide " - or homicide, since there are two of you. Didn't Dick Tracy have a case like this with a villain called "two face"?
    – DanF
    Commented Feb 27, 2017 at 17:00
  • Batman had the villain "Two Face". Dick Tracy had a villain "Haf and Haf". However, it was someone who had half his face burned by acid, not two versions of the same person. Commented Feb 27, 2017 at 17:25

It's a valid מנין only for Christians. After all, the minyan will comprise eight men, your time traveler, and the same guy (אותו האיש).


I see absolutely no problem with this.

One who has davened in one minyan can certainly attend another minyan later on for the same service, and he forms that minyan. That's often done.

As for the same person being there twice - that's also not a problem. There is a rule כל ישראל ערבים זה לזה - Each Jew is responsible for each other. Frequently, we apply this rule to helping or ascertaining that each Jew performs mitzvot properly.

Every Jew should daven with a minyan. The one that davened on time, did his job. The other part of that same person missed the minyan. So, he needs the past one to encourage the later one to be with him to daven in that same minyan, otherwise he may not have that minyan later. They are counted as two people for the minyan because the assumed later one is actually present now as far as the rest of the people can tell. (Only that individual is aware that there are two of himself.) But what counts is the needs of the congregation, here, not one's personal perspective. And so what, if the present and future version look and act identically?


One who has davened in one minyan can certainly attend another minyan later on for the same service, and he forms that minyan. That's often done.

- DanF

Good. Now extend that concept. A person is davining yehidis (alone). He davins, goes back in time to the beginning of the davining, and davins again. And again goes back in time to the beginning of the davining, and again davins, etc, nine times.

So we have the same person, appearing ten times in the same room. Does that count as a minyan and bring down the Schinah?

Maybe not. What about the rule that 6 out of 10 must be "davining" and not just making the minyan. If he goes back in time, after davining once (say, for mincha) is he now re-required to davin the same Mincha? Or, perhaps, if he goes back in time before he davined Mincha, then did he davin yet?

Who davins for the amud? What if he was a chiyuv? Who has Kadima (precedence)?

  • 1
    This doesn't look like an answer, but like a comment to the original question. Note especially that this question is meant to be a joke in the spirit of Adar festivities.
    – mevaqesh
    Commented Feb 27, 2017 at 19:40
  • mevaquesh - sounds like Purim Torah to me. And Purim Torah is no joke. It makes you think, nu? And here we have an example of "if this, also this" (a bigger question) meaning that if a man could go back in time nine time to make a minyan, then one man could go back once to count twice. Did you think about this? And anyway "a comment to the original question" is the Yiddish way of answering a question. So your comment is not a comment. Maybe you have an answer, instead of just a comment? Nu?
    – Joe Cotton
    Commented Feb 27, 2017 at 20:40
  • 2
    Who davins for the amud? What if he was a chiyuv? Who has Kadima (precedence)? Doesnt answer the question. Yiddish or not, to ask another question, use the link: judaism.stackexchange.com/questions/ask.
    – mevaqesh
    Commented Feb 27, 2017 at 20:42
  • This feels more like a comment on DanF's post than an answer to the question. I know you're not new here, but you may not realize that we're a little different from other sites; this isn't a discussion forum but a Q&A site, where we reserve the answer space for answers. You can always How to Ask a new question, and add a link to this post for context. (Besides, that's probably the best way to get feedback on your questions here)
    – MTL
    Commented Feb 28, 2017 at 4:17

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