STANDING UP FOR KERI'AH
Story: Ameimar's grandson died, and he did Keri'ah, not in his son's presence. Then his son came by and he did Keri'ah again, in his presence (see Tosfos for why). Then he remembered that he did the Keri'ah while seated, so he did it again standing.
Question: How do we know Keri'ah must be done standing?
Answer #1: We learn it from Iyov, who stood before he did Keri'ah.
Question: Perhaps although Iyov did this it is not a requirement, just as he pulled out his hair, which is not a requirement.
Answer #2: It is learned from David, who stood for Keri'ah.
Question: Perhaps although David did this it is not a requirement, just as he lay down on the floor, which is not a requirement for mourning, because lying on the floor does not fulfill the requirement of "turning over the bed."
Answer: He didn't literally lie on the floor (that's only a figure of speech); he lay on an upside-down bed, in fulfillment of "turning over the bed." Hence, since we don't find that he did anything extra, we assume that his standing for Keri'ah was required.
A LIST OF THINGS FORBIDDEN TO A MOURNER
A Beraisa lists all the things mourners are forbidden to do:
Anoint the skin with oil
Engage in marital relations
The Beraisa makes an exception to 2:a:6 for a rabbi whose services are required by the public. He may teach Torah.
Another Beraisa limits this exception somewhat. The rabbi may not directly use the services of a Meturgeman (spokesman) when delivering a Shiur.
PUTTING ON TEFILIN FOR A MOURNER
A Beraisa lists two opinions concerning the putting on of Tefilin for a mourner.
According to R. Eliezer, Tefilin may not be put on for the first two days of mourning. Another point he makes is that after this the mourner may keep his Tefilin on even if a new visitor comes to see him.
R. Yehoshua argues with both points. According to him the prohibition to put on Tefilin is only for the first day of mourning. And if a new visitor comes to see the mourner after this he must take off the Tefilin.
The Gemara discusses the Biblical sources for both of the above opinions, whether the most intense period of mourning lasts for two days (like R. Eliezer) or one day (like R. Yehoshua).
Halachah: Ula says the Halachah is like R. Yehoshua with regard to how many days the mourner may not put on Tefilin (i.e., one day), but like R. Eliezer with regard to the issue of removing the Tefilin for new visitors (i.e., he need not remove them from the third day on).
Question: What does Ula hold about removing the Tefilin for new visitors on the second day? (He ruled like R. Eliezer concerning the removal of Tefilin, and R. Eliezer only dealt with the third day and on, for on the second day the Tefilin are not put on at all according to R. Eliezer.)
Answer: Ula holds that the Tefilin must be removed for new visitors on the second day, even if he has to remove them and replace them a hundred times (for a hundred new visitors). A Beraisa supports this view also.
Rava, however, says that once the mourner begins to put on Tefilin (on the second day), he never has to take them off.
Question: Above (20a, 1:b:2) Rava ruled that the first three days of Shiv'ah are especially intense, so he should also say that Tefilin are not put on for three days.
Answer: Rava did not apply this idea when it would end up canceling a Mitzvah (putting on Tefilin).
DIFFERENCES BETWEEN THE FIRST THREE DAYS OF SHIV'AH AND THE REST
Three Beraisos list the following contrasts between the first three days of Shiv'ah and the rest of Shiv'ah:
The first three days the mourner may not do any work, even if he is poor and is sustained by charity. After this he (the poor mourner - Tosfos) may do work privately, in his house, and a woman may spin thread at home.
The first three days a mourner may not go to another mourner's house (for a consolation visit); after this he may go there, and he sits among the mourners, not the consolers.
The first three days a mourner may not give a greeting (or answer one). After that he may answer a greeting but not give one. After the Shiv'ah is over he may give and answer greetings normally.
Question: There is a Beraisa that tells how R. Akiva got up and said words of greeting to those who came to console him. This contradicts the Beraisa in 4:a:3, that says that a mourner may not give a greeting.
Answer: Out of respect for a large group of people it is permitted to give a greeting.
Question: The Beraisa (4:a:3) said that after Shiv'ah the mourner may answer or give a greeting - even during the Shloshim. This is contradicted by another Beraisa. This second Beraisa makes several points:
When encountering a mourner during his Shloshim, one should say words of comfort.
An exception is when the mourner is in mourning for his wife, and he has already married another woman. In that case, no one should enter his house to comfort him at all, and if someone encounters him in the street he should comfort him only with short, curt words. (This is all out of consideration for the feelings of the new wife.)
When encountering a mourner during his Shloshim, one may not greet the mourner. The Gemara assumes that this implies that the mourner may not greet others during his Shloshim either. This contradicts the Beraisa in 4:a:3.
After Shloshim is over, one should not say any words of comfort; it is inappropriate. And at that time the mourner may be greeted by others.
Answer: The assumption made in 4:d:2 is incorrect. Although a mourner should not be greeted by others (in Hebrew a greeting is wishing someone peace - Shalom, and the mourner is not in peace), the mourner may greet others (for they are in peace).
Question: The Beraisa in 4:a:3 said that the mourner after Shiv'ah (even during Shloshim) "may give and answer greetings normally." If he is answering a greeting, then obviously someone has given him a greeting! But giving a greeting to a mourner is explicitly forbidden according to the Beraisa in 4:d:2!
Answer: The greeting was given by someone who didn't realize the mourner was in mourning.
Question: This kind of mistake could happen even during the first three days of Shiv'ah. Why does the Beraisa (4:a:3) say that a mourner may not return a greeting then?
Answer: During the first three days he should not return the greeting but simply say, "I am in mourning." After that time he may respond to the greeting in the normal way.
Question: The Beraisa (4:d:3) said that after Shloshim the mourner should not be comforted, and may be greeted by others. This is contradicted by another Beraisa that states that the mourner should be comforted, and may not be greeted, for the entire year after the death of his relative. (When the year is over, however, it is considered inappropriate to comfort the mourner - although he may be comforted obliquely (Rashi: without mentioning the identity of the deceased) - and the mourner may again be greeted by others).
Answer: The Beraisa (4:j) that speaks in terms of a year-long mourning period is dealing with one who is mourning a parent; the other Beraisa, which speaks of Shloshim (4:d:3) is dealing with one who is mourning another relative.
Question: The Beraisa about parents (4:j), with its year-long period of mourning, allows "oblique comforting" after the year is over. But the other Beraisa, about other relatives (4:d:3), with its Shloshim period, does not mention this option; it implies that after the Shloshim no comforting should be offered at all.
Answer: Although the Beraisa doesn't mention it explicitly, oblique comforting is permitted after Shloshim.