Divorcing a Barren Woman - Meishiv Davar 4:8

A case was brought to the Netziv concerning a man whose wife had not given birth and was now past her childbearing years. While we have a tradition that Sarah gave Hagar to Avraham ten years after they entered Israel and still did not have children, and that this is a template for how long a couple should try having children before the man is to look elsewhere, we also now have to contend with the חרמות דרבינו גרשום which prohibit both polygamy and forced divorce. In this case, the woman refused to accept a get, and thus the question arose as to whether the man had any hope of ever having children.

The Netziv ruled that this was a clear-cut case where the man was entitled to make use of the היתר מאה רבנים, under which he could divorce his wife or at least take on another wife provided that he obtained the signatures of 100 Rabbis from at least three distinct communities. He notes that since the woman has not done anything wrong, the היתר מאה רבנים will allow the man to take on a second wife, and at whatever time that the first wife agrees to accept a get she will receive the full compensation for her ketubah.

Kashrut of Turkey - Meishiv Davar YD 22

In this teshuva from 1884, the Netziv deals with the question of the kashrut status of a bird that had been thought to be some type of a goose, but upon further inspection was sufficiently different in its physical characteristics that it was supposed that it could be an entirely different species. Since birds require a mesorah in order to be declared acceptable to eat, this bird would potentially be deemed non-kosher if it would be found to be a new species altogether. Further complicating the picture is the fact that people had been eating this bird on the assumption that it was essentially a goose, and only now did someone come forward with this question.

The Neztiv begins by noting that unlike other "new" birds which possessed the signs of a kosher bird mentioned in the mishna in Chullin 60 and which had the testimony of someone that it was eaten by Jews elsewhere, the bird in question here was significantly different from other kosher birds, and was not known to be eaten elsewhere. He then mentions the hybridization test, which is mentioned in the Gemara in Bechorot 7 and which claims that kosher and non-kosher species cannot produce live young. Thus, if two different animals can produce children, and one is known to be kosher, then the other one should be kosher as well. While the Netziv feels that this rule may not be 100 percent accurate, he does qualify it by saying that if a bird from one species will mate with a bird from another one in the presence of birds of his own species then that is an indication that they are all of the same species.

However, the Netziv concludes that this is all academic, and would only be relevant if the question had been brought before people had begun eating this bird. However, once the bird has been eaten on a regular basis, only proof that it is not kosher (such as proof that it is a predator) would disqualify it from being an acceptable bird to eat.

[While it is not clear what bird the Netziv is discussing, this issue is one of the key issues involved in the eating of turkey, which, as a New World bird lacked a mesorah for its kashrut status, but which was ultimately subsumed under the mesorah of chickens, ducks, and geese - and once it gained acceptance it never lost it.]

Tzitzit check - Meishiv Davar 1:2

In this teshuva written to the Chafetz Chaim, the Netziv takes issue with a psak written in the Mishna Berura (which was written by the Chafetz Chaim) where he writes that if one has a tallit which is pasul for some reason or another then he may not go outside on Shabbat with that tallit (in a place with no eiruv), and if he does he will be in violation of the prohibition of carrying on Shabbat (presumably he is considered to be carrying the strings).

The Netziv notes that the view of the Mishna Berura is against the overwhelming majority of Rishonim and Acharonim. According to Rashi, if one had techeilet that was not fit for the mitzva then he would violate the prohibition of carrying, but if one only has white strings they are not considered to be that important and thus there is no prohibition (remember, the Netziv lived before the revival of techeilet). According to Tosafot, there would only be a violation if one had a garment with three tzitzit made already and the fourth was missing.

The Netziv does point out that Rav Akiva Eiger leaves open the possibility that one could violate Shabbat with any form of psul in his tzitzit, but the Netziv counters that other than that possibility, there does not seem to be any major support for the position of the Mishna Berura. There also seems to be a view in the Rishonim that tzitzit should not be worn at all on Shabbat for this reason, but the Rosh rejects this as an unnecessary stringency.

Shatnez and Tzitzit - Meishiv Davar 1:1

In this first teshuva in this collection, the Netziv deals with a statement of the Magen Avraham who writes that one can put wool tzitzit on a linen tallit (in seeming violation of the laws of shatnez) if the corners of the tallit have leather patches on them. He initially raises two questions on this position. First, whether or not leather serves as a barrier vis-a-vis the laws of shatnez is actually a debate in the mishna in Kilayim. Second, there is a view that the tzitzit have to be made out of the same material as the corner from which they hang, and if that corner is made out of leather then there would be no obligation to have tzitzit there in the first place.

The Netziv then adduces a gemara in Yevamot which proves from a pasuk that shatnez is not a problem when it comes to tzitzit. However, he responds that the pasuk should not be needed if the leather patch can serve as an effective barrier. In other words, which is the true reason why this set-up should be permitted?

The Netziv spends some time on whether having or not having techeilet makes a difference (he says it does not), and whether this would be considered to be a situation of מצוה הבאה בעבירה. In the end, he concludes that there is no need to make a decree restricting one from making such a tallit, since if someone takes the time and effort to add the leather patches the chances are that we no longer have to worry about shatnez in that case.