Resources for Yevamos daf 48
1. The גמרא says that a גר תושב cannot be מחלל שבת. רש"י in ד"ה גר תושב says that every גר תושב is חייב in שמירת שבת since someone who doesn’t keep Shabbos it is as if they are עובד עבודת כוכבים so in that sense it is included in the שבע מצוות בני נח. תוספות in ד"ה גר תושב asks that this cannot possibly be true since if every נכרי needs to keep Shabbos then there are really שמונה מצוות בני נח! Furthermore, the גמרא tells us that גוי ששבת חייב מיתה! Rather, תוספות says the גמרא means that a גר תושב cannot do מלאכה for a ישראל, but he is certainly allowed to do מלאכה for himself. In explanation of רש"י, the ערוך לנר in ד"ה זה גר תושב explains that there is a fundamental difference between a גר תושב and every other נכרי. A regular נכרי just has to keep שבע מצוות and nothing more. Even רש"י would agree that he can and must be מחלל שבת. However, a גר תושב is someone who accepted to keep שבע מצוות like a Yid. Therefore, for him שבע מצוות includes שמירת שבת because for a Yid being מחלל שבת is כעובד עבודה זרה. This also answers תוספות’s question about גוי ששבת since that is not, according to רש"י, talking about a גר תושב but rather a regular נכרי.
2. The גמרא says in the name of רבי חנינא that the reason גרים suffer בזמן הזה is because they didn’t keep שבע מצוות when they were נכרים. However, ר׳ יוסי disagrees since גר שנתגייר כקטן שנולד דמי so they cannot be held responsible for what they did in their past. Rather, they suffer because they aren’t מדקדק במצוות. The ערוך לנר asks that everyone agrees to the concept of גר שנתגייר כקטן שנולד דמי, so how could רבי חנינא have said that they are punished for what they did before they converted? He answers that רבי חנינא held that the concept of כקטן שנולד דמי means that we view the person as if they died and were reborn (similar to the concept of a גלגול). Therefore, even though they aren’t going to be considered related to anyone from their past life, it doesn’t mean that they aren’t responsible for their past עבירות. On the other hand, ר׳ יוסי holds that it is if their previous life did not exist at all and they aren’t responsible for what they did before they converted. There is an important corollary to our גמרא in סנהדרין דף ע"א ע"א. There ר׳ חנינא says that a בן נח שבירך את השם and then converted is פּטור. תוספות there in ד"ה בן נח asks on this from our גמרא which says that it’s a מחלוקת תנאים whether a גר is פּטור from things he did as a נכרי so why does the ר׳ חנינא say it as if everyone agrees? He answers that our גמרא in יבמות is only referring to דיני שמים but the גמרא in סנהדרין is talking about בדיני אדם and בדיני אדם everyone agrees that they are פּטור. Based on this the ערוך לנר has another possibility—that רבי חנינא held that גר שנתגייר כקטן שנולד דמי only applies בדיני אדם but not בדיני שמים and ר׳ יוסי holds it applies even בדיני שמים.
3. The גמרא quotes אחרים as saying that the reason גרים suffer is because they didn’t become Yidden sooner. The גמרא seems to need explanation. How could they be punished if they weren’t obligated to convert? The אהבת איתן (in the עין יעקב) explains that all the נשמות of the גרים were at הר סיני. Therefore, they should have come sooner since they already had the proclivity to do so. The Steipler Gaon זצ"ל in קריינא דאיגרתא in חלק ב׳ עמוד דש asks how they could be punished for not coming sooner when we just said that a גר cant be punished בדיני שמים for what he did before he became a yid? He answers with a יסוד: the שבע מצוות that are incumbent on בני נח are not the same מצוות that are incumbent on Yidden. Therefore, now that they are Yidden they can’t be held responsible for violating the שבע מצוות since they are no longer בני נח and their חיוב in those מצוות is no longer relevant to them. However, the desire to be a Yid is something that is still relevant to him even now so he can still be held responsible at this time.
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