Saw interesting Torah talk at Shaarei Shamayim (in Toronto, where I am living for another few mos.) a few days ago. Guest rabbi was talking about whether grape juice may be used for Pesach seder. The issue is still halachically disputed; the majority rule even among O rabbis is yes, but some eminent poskim on the other side. Two issues:
1. Talmud ambiguous as to whether “cooked wine” (a category which includes grape juice) may be used. The Talmud says that only wine used for libations can be used (implying no cooked wine) but gives examples other than cooked wine. Medieval commentators split.
2. Talmud says drinking four cups with undiluted wine not ideal (because wine was mixed with water then since otherwise too strong), and Rava says “He has fulfilled the aspect of wine, but not of freedom.” Rashbam says “only diluted wine is distinguished.’ Anti-grape juice poskim interpret this to mean that “undistinguished” wine is not OK, and grape juice is too “undistinguished.”
Rambam says that “These four cups must be diluted to guarantee a pleasant drink. Everything depends on the wine and the taste of the person drinking.” Pro-grape juice poskim (incl. J. Soloveitchik but not Moshe Feinstein) say that wine isn’t appropriate for everyone so grape juice adequate backup.
