How do we know Shabbat is on Shabbat?

[Eliezer Ben Avraham]

I was just thinking like how do we know that what we consider the 7th day (Saturday) is actually what G-d considered the 7th day?
How do we know that Shabbat isn't really on Friday (like friday is really the 7th day of the week according to G-d)?
I was also thinking like about the Six day war in terms of this idea, and does anyone think it's possible that June 12th 1967 (Which was a Sunday) is actually the 7th day of the week? like in 6 days G-d worked for us and then he rested?
I was just thinking about these things, not trying to create trouble or anything but just a bit curious.

[Tzvi Ben Roshel1]

because it was allways observed since Moshe by the majority of the nation.

[q_q_]

I was just thinking like how do we know that what we consider the 7th day (Saturday) is actually what G-d considered the 7th day?
How do we know that Shabbat isn't really on Friday (like friday is really the 7th day of the week according to G-d)?
I was also thinking like about the Six day war in terms of this idea, and does anyone think it's possible that June 12th 1967 (Which was a Sunday) is actually the 7th day of the week? like in 6 days G-d worked for us and then he rested?
I was just thinking about these things, not trying to create trouble or anything but just a bit curious.

I heard an answer that it is a tradition going back from the time of Adam. Passed down and accepted, if not  by the whole world, then all over the world.

[MassuhDGoodName]

Re:  "...How do we know that Shabbat isn't really on Friday?..."

That's an easy one to answer!

The interval period of time beginning when the Forum closes, and ending when the Forum reopens...

That is when the Sabbath is!

Accept no substitutes!

[Lubab]

Re:  "...How do we know that Shabbat isn't really on Friday?..."

That's an easy one to answer!

The interval period of time beginning when the Forum closes, and ending when the Forum reopens...

That is when the Sabbath is!

Accept no substitutes!

 

[Uziyahu]

Another simple question...

Answer: Because Jews somewhere in the world have been observing Shabbat since it was instituted as law.  If Jews in one place were compelled to work on Shabbat, Jews elsewhere would have corrected them when they became free to observe it, again.

[Eliezer Ben Avraham]

Another simple question...

Answer: Because Jews somewhere in the world have been observing Shabbat since it was instituted as law.  If Jews in one place were compelled to work on Shabbat, Jews elsewhere would have corrected them when they became free to observe it, again.

"but how do we know we didn't skip a day at some point?", was the original question, but I guess that is unrealistic

[Tzvi Ben Roshel1]

Its also kinda of cool and Thank G-d that everyone in the World has a 7 day per week system. - probably becuase that was the tradition that was passed down from Noah( who learned it from his predecessors and back to Adam who got it from G-d creating the world in 7 days).
 Thank G-d its like this, becuase if not, then their would be disorder for us Jews and really inconvenient.

[Eliezer Ben Avraham]

Its also kinda of cool and Thank G-d that everyone in the World has a 7 day per week system. - probably becuase that was the tradition that was passed down from Noah( who learned it from his predecessors and back to Adam who got it from G-d creating the world in 7 days).
 Thank G-d its like this, becuase if not, then their would be disorder for us Jews and really inconvenient.

Definitely. Nonetheless, we would manage to figure it out

[Raulmarrio2000]

Just a similar question....one version of the Ten Commandments mentions Exodus from Egypt as a reason for Jews to keep Shabat, and the first day of Peisach is called Shabat also. Would it be possible that in Moses' time Nissan 15th was always on Shabat? If the calendar was made by observing the New Moon at that time, why isn't even ONE occassion in the whole Tanch when Jews had doubts about the calendar? Some days the sky must have been cloudy!!!!! What if at that time the sun and the moon were syncronized, and the months had 28 exact days and the solar years exactly 12 months??? Would it be possible?

[Lubab]

Just a similar question....one version of the Ten Commandments mentions Exodus from Egypt as a reason for Jews to keep Shabat, and the first day of Peisach is called Shabat also. Would it be possible that in Moses' time Nissan 15th was always on Shabat? If the calendar was made by observing the New Moon at that time, why isn't even ONE occassion in the whole Tanch when Jews had doubts about the calendar? Some days the sky must have been cloudy!!!!! What if at that time the sun and the moon were syncronized, and the months had 28 exact days and the solar years exactly 12 months??? Would it be possible?

Jewish law has a lot detailed laws about what to do when the sky is cloudy. It's not a big problem.

[q_q_]

Just a similar question....one version of the Ten Commandments mentions Exodus from Egypt as a reason for Jews to keep Shabat, and the first day of Peisach is called Shabat also. Would it be possible that in Moses' time Nissan 15th was always on Shabat? If the calendar was made by observing the New Moon at that time, why isn't even ONE occassion in the whole Tanch when Jews had doubts about the calendar? Some days the sky must have been cloudy!!!!! What if at that time the sun and the moon were syncronized, and the months had 28 exact days and the solar years exactly 12 months??? Would it be possible?

15 Nissan of The Exodus was a Thursday.

yaakov: what pasukim show that?


raul: I would have to check it again..  Do you think the first day of pesach was on shabbat?  I remember something about the tenach saying about a day being shabbat, and the oral tradition says it means a yom tov.. Or something.  I think that was while talking about counting the omer. The first shabbat after pesach..     What is it that says that the first day pesach was shabbat?

I am not saying it doesn't say that.. I just haven't read/studied it for a while

[Tzvi Ben Roshel1]

I think Shavuot was on Shabb-t, but I could be wrong.

[q_q_]

16th nissan (first day of the omer / 2nd day pesach) is same day of the week as shavuot.

note: in diaspora or israel, we count from the 16th, one can verify this because if we didn`t then shavuot would not come out on the right day (the 50th day, the day after the 49th day of the omer).
In diaspora, the 16th is chol hamoed. In israel, it is yom tov. But still, we count from the 16th.

there is a pasuk, as suggested by raul, that says you count the omer from the day after shabbat. oral tradition says we count from the first day of pesach, and I think relates it to that verse, saying shabbat here refers to pesach yom tov.   It may be, as raul said, that first day pesach was shabbat at that time. (though I would say, perhaps that only refers to the first time). 

If that is the case though that the 15th was Saturday.
Then the 16th was sunday, and shavuot was sunday.

I have found a few webpages that say that according to the gemara, the Torah was given on shabbat. So shavuot was on shabbat. 
Shavuot is the "50th day". The same day of the week as the first day of the omer. (see kaluach software, for the pattern)  1st, 8th, 15th, +7, e.t.c. of the omer, up to "50th". Are same day of the week.
So the 16th nissan was saturday.
That makes the 15th, sunday.

So judging by the gemara, the other ideas, raul`s , that 16th was sunday, or Yaakov`s that 15th was thursday,   seem wrong.   Raul`s argument was just a suggestion based on a pasuk.
Yaakov, what is your source for saying the 15th was a thursday?

note- there are some variables here.. if the torah was given at night(I think it was given in the morning, but would have to check, rashi quotes some gemara there).. But another variable is the teaching that in those days, jewish days began in the morning not at night.  So for example, when the tenach says "on the 14th, in the night" , and at another point says, on the 15th.  It is saying the same thing. Because in those days, the 14th in the night, was the end of the 14th. And later, we started counting days from the night. So on the 15th/ night of the 15th, the start of the 15th.