Stopping for Kedusha

Question

The shul next to my house has ongoing minyanim for Mincha on Shabbos afternoon. There are always two minyanim at one time, one inside the bais medrash and one in the room next to it. The second room does not have an aron kodesh, so the person who gets hotza’ah vehachnasah has to bring the Sefer Torah for krias haTorah from the bais medrash and return it there afterwards.

Last Shabbos, a man came into the bais medrash to take a Sefer Torah to the minyan in the other room, but on his way out, while he was holding the Sefer Torah, the minyan in the bais medrash started Kedusha. In such a scenario, what should the man with the Sefer Torah from the other minyan do? Should he answer Kedusha, which will cause tircha detzibura, since the minyan in the other room will need to wait, or in such a scenario does tircha detzibura override reciting Kedusha?

Yehuda K.

Bais Knesses Imrei Shefer, Har Nof

Rav Auerbach 

The halacha is that if one is sitting in a shul where Kedusha is being recited, he must join in with them (Shulchan Aruch 125:2). If he is outside the shul, there is a dispute amongst the poskim whether he must should stop what he is doing to recite Kedusha. My father ruled that if one is outside the shul and he is not involved in this minyan, he does not have to stop, but it is praiseworthy to do so (see Halichos Shlomo 9[8]).  

Based on these guidelines, one would think that since the person carrying the Sefer Torah is in the room with the minyan, he is obligated to stop and recite Kedusha. However, the Gemara in Brachos (61a) rules that if one is passing a shul where a minyan is taking place and he does not go in, it appears like he is a kofer and disgracing the shul. The Gemara concludes that when this person is wearing tefillin, he is allowed to walk by the minyan, since his tefillin prove his belief in the Almighty.

The principle that we learn from the Gemara in Brachos can be applied to our case. Since the man is holding a Sefer Torah, it’s obvious that he is in middle of davening Mincha and not disgracing the minyan reciting Kedusha. Once he is allowed to leave the bais medrash, he should also not say the words of Kedusha while he is walking, because one is meant to say Kedusha while standing still.