Q. If I was invited to partake of shalosh seudos (third meal of Shabbos) by a certain rabbi, but I know that the rabbi is not makpid (particular) on starting before shkia, (sunset), whereas I am very makpid, what should I do? Should I simply decline the invitation and offer some excuse, as I do not wish to rely on b’dieveds?
A. Mishna Berura (299: 1) maintains that although in principle one should not eat during Shabbos after the beginning of sunset, for the purpose of eating shalosh seudos, if one did not start before the shekiah as required, bedieved he should still eat after, until a half an hour before the end of day.
Teshuvos Vehanhogos (2: 203) mentions that the Brisker Rov and Horav A. Kotler zt’l, were not always particular to begin eating shalosh seudos before the shekiah
However, some Poskim are stringent. Dinim Vehanhogos (10) quotes Chazon Ish, that he would not permit washing even bedieved, after the shekia, Yisroel Vehazmanim (1: 31), adds that he would even permit davening mincha without a minyan if necessary. A similar opinion is mentioned in Orchos Rabbenu in regard to Horav Y. Kanievsky zt’l.
Horav Shlomo Miller’s Shlit’a opinion is that if declining the invitation would hurt the feelings of the Rabbi, it may be correct to follow the bedieved opinion of the Mishna Berura above. The Rov pointed out to the Biur Halocho (415; D’H Veim) regarding an eiruv placed during bein hashmoshos, that if the time fits Rabi Yosi’s opinion, although we don’t rule like him, it would be bedieved permitted. The Rov added that one may also wash hands and start the third meal before the shekia at home and eat there an egg-full volume of challah, having in mind to continue at the home of the Rabbi.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a