1) There is a proof given by the Sha'ar HaMelech, Hilchos Ishus 9:16, that if somebody believes that an item is forbidden he is not allowed to give it to somebody else who believes it is permiited. This is from the Shitah Mekubetzes Nedarim 90b DH Matn'. The Mishnah there tells us that if a wife says she has been unfaithful we do not believe her since we suspect that in reality she wants to marry someone else and has invented a way of forcing her present husband to divorce her. We say that she must stay with her husband.

2) The Shitah Mekubetzes there cites the Shittah who asks how is she allowed to stay with her husband since she has said that she is forbidden to him, and therefore transgesses Lifeni Iver every time she is with him?! Shittah answers that there is no prohibition of Lifnei Iver because she is being forced by the Beis Din to have relations with him. So even if the wife is actually telling the truth when she says she was unfaithful and she really is forbidden to her husband, there still is no Lifnei Iver since Lifnei Iver only applies when A is trying to cause B to sin; not when A is being forced by others to cause B to sin.

3) Sha'ar Hamelech writes that one learns from the Shittah that if not for the fact that she was being forced, there would be a problem of Lifnei Iver. Even though the husband believes that she is permitted to him; since he says that she invented the story about being unfaithful; she would not be allowed voluntarily to have relations with him if she genuinely thinks she is forbidden. We learn that if A holds the item is forbidden he is not allowed voluntarily to give it to B even though B thinks it is permitted.

KOL TUV

Dovid Bloom

The opinion of the Ksav Sofer:

1) In Teshuvas Ksav Sofer Orach Chaim #66 DH veHineh HaSHAH'M he cites the Sha'ar Hamelech and disagrees with him. He writes that the scenario of the Shitah Mekubetzes in Nedarim and the scenarios where there are Halachic disputes on certain matters are very different. In Nedarim she knows for sure that she is forbidden to him, but he does not have to believe her and can say that she is lying. But in her mind there is no doubt. This is not similar to Halachic disputes where there are 2 major Torah scholars who have delved into the matter and emerged with their respective opinions. Ksav Sofer writes that this means that one cannot say for sure that either of them is wrong, and it therefore follows that even the Posek who is machmir, together with his follwers, can give the item to the person who is lenient, because it is not certain that he is not correct, and it therefore follows that there is no issue of Lifnei Iver involved since a major Posek is lenient.

2) I would like to narrow somewhat the difference between Sha'ar Hamelech and Ksav Sofer. It all depends how confident the stringent opinion is that he really is correct. The Sha'ar Hamelech refers to a scenario where the stringent Posek is totally certain that the Halacha follows him. Therefore this is similar to the woman who knew for sure she had been unfaithful. I want to say that Ksav Sofer would agree to Shaar Hamelech in such a scenario but he understands that in most Halachic disputes there is not a such sharp difference between the 2 sides that we would say that one opinion is 100% sure that the other opinion is wrong.

Dovid Bloom

Rav Chaim Volozhiner about giving food that was under the bed to others:-

1) I think that possibly the account about the Vilna Gaon letting others drink Mayim Geluyim may in fact not refer to Mayim Geluyim but rather to food or drink that was placed under the bed. The reason I say this is because in the sefer Chochmas Adam Klal 68 (about things that are forbidden because of danger) in Binas Adam #63 he writes that he heard that the Vilna Gaon commanded that if radish was placed under the bed it should be cut up into small pieces and thrown away so that nobody could benefit from it. However in the sefer "Kol Hakosuv LeChaim" (which is a collection of Halachos and customs in the name of Rav Chaim Volozhin) page 171, in note 126, it is related that whilst the Gra was himself stringent on this, he nevertheless was lenient for others and ordered that the drinks that had been under the bed should be given to them.

2) However, as you say Yishai, this may be because there are opinions that bedieved food or drink that was left under the bed is permiitted. This is in fact stated by Rav Chaim Kanyevsky shlita, in Ta'ama deKra page 23(#28), that the Chazon Ish was particular at home not to eat food which had been under the bed, but ordered that it should be given to poor people and shouild not be destroyed since according to the Din the food is permitted.

Good Shabbos

Dovid Bloom

An insight in the name of Rav Shlomo Zalman Auerbach zt'l:-

1) I found, bs'd, what I think is a support for what I wrote in my second answer, in item 2). This is from sefer Maor HaShabbos (by Rabbi Moshe Adler) vol.1 page 463. The question is connected to the dispute between the Mechaber of the Shulchan Aruch, and between the Rema; if there is an additional prohibition of cooking on Shabbos something (which contains liquid) which has been fully cooked and then cooled down and is now only lukewarm. The Rema Orach Chaim 318:15 writes that the custom is to be lenient if it has not totally cooled down. Mishneh Berurah #99 writes that even though according to the Mechaber, if it has cooled a little and is no longer Yad Soledes, there is a prohibition against cooking again, however the custom is to be lenient because people rely on the Mekilim as long as it is not totally cold. In short, Sefardim are machmir about this, because they follow the Mechaber of the Shulchan Aruch, whilst Ashkenazim are lenient since they follow the Rema.

2) The question is:- if the fully cooked liquid food of a Sefardi cooled down and is now only lukewarm, may he ask an Ashkenazi friend to put it back on the heat for him? Rav Shlomo Zalman Auerbach answered that it depends why the Sefardi is stringent on this matter. If it is because he has studied seriously the question and has come to the conclusion that the Halacha indeed follows the Mechaber (Beit Yosef) of Shulchan Aruch concerning this issue; then it makes sense to say that he may not ask the Ashkenazi friend to rely on the Rema. On the other hand if the Sefardi is only machmir because this is the custom of his parents and his teachers, then it seems that he may ask the Ashkenazi to re-heat it since the Sefardi really considers this question to be merely a matter of custom.

3) It seems to me that this fits well, bs'd, with what I wrote above in the name of the Shaar Hamelech and the Ksav Sofer. The Shaar Hamelech compares the question of smoking on Yomtov to the issue of the woman who knew she was unfaithful. Since she knows for sure, this can be compared to someone who is convinced that one may not smoke on Yomtov. It follows that, because of Lifnei Iver, such a person may not give a cigarette to someone who relies on the lenient opinion. On the other hand, if the person who does not smoke on Yomtov merely has this practice because that is what his Rabbi rules, but he is aware that other Halachic opinions permit this and he himself has no strong views on the matter, then this is what the Ksav Sofer refers to when he writes that the entire issue is one of doubt so there is no prohibition of Lifnei Iver involved when he gives the item to the friend following the lenient opinion.

4) For this reason, I find it hard to believe the story about the Mabit. The Mabit must have strongly believed that the Halacha is that the Peiros of Nochri possess kedusha in the Shemitah year. Therefore it seems to me that to hand them over to someone who would not treat them with kedusha, would represent a transgression of Lifnei Iver.

Shavua Tov

Dovid Bloom