I have thought for a long time if you are learning, you don't need to interrupt for kadish and Kedusha.
This was because I learned in (Tur טור ארח חיים laws of Suka תר''ם) the Beit Yosef who brings down this idea that one who is involved in one mitzvah does not have to interpret for another mitzvah even when he can easily do both.
I found some support for this idea in the Gra that when one is learning Torah he can interrupt to do a mitzvah that no one else can do--but he does not have to. [See the Mishna in Peah]
For the general public I want to explain what I mean here:
In general, a person that is involved in one mitzvah is not required to do another mitzvah.
For example if a person gets married, then he and the groups of friends that are there to make merry are not required to sit in a suka for the whole seven days of marriage festivity [according to the Rambam.]
Another principle is learning Torah is a mitzvah. Torah in this context means the Old Testament or the Talmud.When one is learning Torah, he is allowed to stop to do another mitzvah, but he does not have to.{Gra}. Thus in a synagogue when people get up to say kaddish or kedusha if you are learning, you don't have to answer. All the more so since this usually happens after the time for prayer which is from dawn until 4 hours later. After that only if one had an unforeseen emergency can he pray until noon. Other than that the pray (blessings in vain) and one is not even allowed to answer Amen.
This came up because of my learning partner who often has to interrupt to answer, and I told him he does not have to answer.
The truth be told there is a much better support for this idea. It is in the Talmud Shavuot pg 43 and 43b with the whole idea there of the "penny of Rav Joseph". [Pruta shel Rav Joseph]. That is when one is in possession of a lost object, he is not obligated to give a penny to a poor person because he has to watch the object. And Tosphot explains there that even Raba does not disagree with this. Rather he says that just because a poor person might come, we do not say that he is a guard that is paid. The reason is a poor person might not come. So we see everyone agrees העוסק המצווה פטור מן המצווה one involved in one mitzvah does not have to stop in order to do another mitzvah even if the second mitzvah is much more important and even if not doing it involves a prohibition of לא תתעלם
This was because I learned in (Tur טור ארח חיים laws of Suka תר''ם) the Beit Yosef who brings down this idea that one who is involved in one mitzvah does not have to interpret for another mitzvah even when he can easily do both.
I found some support for this idea in the Gra that when one is learning Torah he can interrupt to do a mitzvah that no one else can do--but he does not have to. [See the Mishna in Peah]
For the general public I want to explain what I mean here:
In general, a person that is involved in one mitzvah is not required to do another mitzvah.
For example if a person gets married, then he and the groups of friends that are there to make merry are not required to sit in a suka for the whole seven days of marriage festivity [according to the Rambam.]
Another principle is learning Torah is a mitzvah. Torah in this context means the Old Testament or the Talmud.When one is learning Torah, he is allowed to stop to do another mitzvah, but he does not have to.{Gra}. Thus in a synagogue when people get up to say kaddish or kedusha if you are learning, you don't have to answer. All the more so since this usually happens after the time for prayer which is from dawn until 4 hours later. After that only if one had an unforeseen emergency can he pray until noon. Other than that the pray (blessings in vain) and one is not even allowed to answer Amen.
This came up because of my learning partner who often has to interrupt to answer, and I told him he does not have to answer.
The truth be told there is a much better support for this idea. It is in the Talmud Shavuot pg 43 and 43b with the whole idea there of the "penny of Rav Joseph". [Pruta shel Rav Joseph]. That is when one is in possession of a lost object, he is not obligated to give a penny to a poor person because he has to watch the object. And Tosphot explains there that even Raba does not disagree with this. Rather he says that just because a poor person might come, we do not say that he is a guard that is paid. The reason is a poor person might not come. So we see everyone agrees העוסק המצווה פטור מן המצווה one involved in one mitzvah does not have to stop in order to do another mitzvah even if the second mitzvah is much more important and even if not doing it involves a prohibition of לא תתעלם
