אין אדם מקנה דבר שלא בא לעולם.
One can not cause to acquire something that is not yet in one's possession. Yevamot 93.
R Meir says one can and this seems to depend on Aristotle's idea of the sea battle that will take place tomorrow. That is though he can not cause it to be acquired now but it is true now that it will be acquired.
Rav agrees with R. Meir if he says "from now." There is a three way argument between Tosphot, the Rashba and the Ramban what that means.


See Rambam laws of Acquisition 22:1

Serving in IDF (Israeli Defense Force)  is important from several angles. The major angle is the same reason why the Jewish community in Safed that was started by the disciples of the Gra organized a community protection force. It does not have to be any more profound than that. It also helps to know the important fact that both Reb Moshe Feinstein and Reb Aaron Kotler said in Israel "דינא דמלכותא דינא" (the law of the country is the law)
But it might be more profound that that.
But my claim is more simple. If all we had would be Reb Moshe and Reb Aaron Kotler that would be enough to establish the law.

My own feeling about this subject is mainly based on the little bit of reading I did about Jewish Communities during the Middle Ages. [That is in the Teshuvot of the teacher of the Rosh Rav Meir from Rotenberg]. Still there are troubles in Israel because of the Sephardim trying to get rid of the Ashkenazim. Not all but enough to make it worthwhile to be aware of this problem.

The issue of Christianity comes up from time to time.  The basic approach I have towards this is based on Rav Avraham Abulafia--a mystic from the Middle Ages who said about Jesus some pretty positive things.[The idea of Rav Abulafia seems to be that he was the messiah son of Joseph that is mentioned in the Gemara Suka.]  Not that that makes the basic approaches of Christianity right, but it does show a different side to the whole issue.  

In other words--the problems are well known--Paul certainly opened the gates to an approach which was not the approach of Jesus at all. But on the other the general attitude that I have encountered is that one has to say and believe that Jesus was a bad guy, and that is the one and only thing that makes one kosher--that also seems wrong. It does not seem to reflect on a commitment to truth but rather to ideology.

From my point of view, Jesus never said he was God nor claimed any kind of worship. It is hard to see from where that belief comes from the in New Testament. He did claim to be a son of God. But that is not different from what God said to Moses to tell Pharaoh, "My son my first born is Israel". Nor does it seem all that different from the verse in Deuteronomy; "You are the children of the Lord your God, Do not make a tattoo on your bodies." 

Nor did Jesus nullify any commandments at all,  even of the words of the scribes. "The scribes sit on teh seat of Moses and so all that they teach and command that you must do."

However it also seems that the issue is more important than what could be swept under the carpet. Certain people are sent into this world to bring some kind of great good into the world. Like Moses. And from my perspective there are certain positive things associated with Jesus that can not be gotten through any other channel. 

[So in so far as Christians learn and emulate Jesus they are right. But in so far as they worship him, that  is wrong. One should worship God alone.]

Since it is clear that the Rambam holds the פטור of מתעסק בשבת is because מלאכת מחשבת אסרה תורה then how does he understand Abyee in Sanhedrin 62b? Abyee says one who bows down to a statue and he did not know it is an idol לא כלום הוא

God is simply beyond pure Reason and reaching Him is possible,-- but not by means of having a right set of beliefs

I realize that to cleave to God is not as exclusive as having the right set of beliefs. But nor is it irrelevant to one's beliefs.
The way I see it is that it is really in the realm of the Ding An Sich as Schopenhauer would put it. That is to say God is simply beyond pure Reason and reaching Him is possible,-- but not by means of having a right set of beliefs. Cleaving to God is possible even with mistaken beliefs. And even with right beliefs one can be far from God.
The Rambam already in the Guide wrote that people have no inherent sense of the Divine Law or Moral Law. We depend on the one time revelation on Mount Sinai. A Unique event in History.
That is,-- there is no access by means of reason. But there is access by faith. [What Leonard Nelson would call immediate non intuitive knowledge. I.e. known immediately not through anything nor derived nor senses.

I feel there were great people that had basic belief in Torah, and yet maybe had a few things off. Still I think there were connected with the Divine Realm. I do not think purity of belief is much of a proof or criterion for being kosher. The Sitra Achra has plenty of agents that can get through that test.

השותף ללמידה שלי טען כי אחד יכול להיות מחויב חטאת עבור מתעסק (טעות בעובדות), רק כאשר יש הנאה.

My learning partner argued that one can be obligated a sin offering for מתעסק a mistake in the facts, only when there is הנאה pleasure. The normal case of a חטאת is when there is  a mistake in law, not in the physical facts.
Later I saw that this can not be the case to the רמב''ם as רב שך goes into  in laws of איסורי ביאה א:י''ב. What my learning partner suggested is in fact the opinion of תוספות and all other ראשונים but not the רמב''ם.
To make things short:
The רמב''ם in three places says the reason מתעסק בשבת is not obligated in a sin offering is because מלאכת מחשבת אסרה תורה. He does not say is is because he was not נהנה These places are ה' שגגות פרק ב' ה''ז פרק ז' הי''א and also in פירוש המשנה כריתות פרק ספק אכל. In all three places the  רמב''ם says the reason מתעסק בשבת is פטור  is because מלאכת מחשבת אסרה תורה and he says nothing about whether he was נהנה or not.
However נהנה even to the  רמב''ם can make one a מזיד in order to be obligated in lashes.

השותף ללמידה שלי טען כי אחד יכול להיות מחויב חטאת עבור מתעסק (טעות בעובדות), רק כאשר יש הנאה. המקרה הרגיל של חטאת הוא כאשר יש טעות במשפט, לא בעובדה הפיזית. רק אחר כך הבנתי שזה לא יכול להיות כן לרמב''ם כמו רב שך נכנס בזה בה' איסורי ביאה א: י''ב. מה שותף הלמידה שלי הציע הוא למעשה דעת תוספות והראשונים אבל לא הרמב''ם. כדי לעשות הדברים קצרים. הרמב''ם בשלושה מקומות אומר שהסיבה מתעסק בשבת אינו מחויב בחטאת היא משום מלאכת מחשבת אסרה תורה. הוא לא אומר שהוא משום שהוא לא נהנה. מקומות אלה הם ה' שגגות פרק ב" ה''ז, פרק ז' הי''א וגם בפירוש המשנה כריתות פרק ספק אכל. בכל שלושת המקומות האלה הרמב''ם אומר שהסיבה מתעסק בשבת הוא פטור היא משום מלאכת מחשבת אסרה תורה. והוא לא אומר כלום לגבי השאלה אם הוא היה נהנה או לא. עם זאת נהנה אפילו לרמב''ם יכול לעשות אחד למזיד כדי להיות מחוייב במלקות.

He argued that one can be obligated a sin offering for מתעסק [a mistake in the facts,] only when there is הנאה pleasure.. That is the normal case of a sin offering is when there is a mistake in law, not in the physical facts.

I saw that I had written something in my notes on Shas (Gemara. That is the Oral Law) in the name of my learning partner. He argued that one can be obligated a sin offering for מתעסק [a mistake in the facts,] only when there is הנאה pleasure.. That is the normal case of a sin offering is when there is  a mistake in law, not in the physical facts.
Later I saw that this can not be the case to the Rambam. Rav Shach goes into this in laws of איסורי ביאה א:י''ב. What my learning partner suggested is in fact the opinion of Tosphot and all other rishonim but not the Rambam.
To make things short:
The Rambam in three places says the reason מתעסק בשבת is not obligated in a sin offering is because מלאכת מחשבת אסרה תורה. He does not say is is because he was not נהנה (get pleasure.) ה' שגגות פרק ב' ה''ז פרק ז' הי''א and also in פירוש המשנה כריתות פרק ספק אכל in all three places the rambam says the reason מתעסק בשבת is פטור  is because מלאכת מחשבת אסרה תורה and he says nothing about whether he was נהנה or not.
However נהנה even to the Rambam can make one a מזיד in order to be obligated in lashes.
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