A mourner is forbidden to study Torah, for it is written, "The precepts of Adonoy, are upright, rejoicing the heart."¹ 19:9. and a mourner is forbidden to rejoice. He is forbidden to study the Scriptures, the Mishnah, and the Talmud, including the laws and Aggadah. But he is permitted to read the book of Job, Lamentations, and the mournful sections of Jeremiah. In the Talmud, he may study chapter, V'eelu Megalchin,². dealing with the laws of the excommunicated and the mourner, and also Maseches Semachos. And in the Seforim (books) of Halachah (laws), he may study the laws concerning mourning. However, he is forbidden to probe and analyze even the subjects he is permitted to study.

footnotes: ¹ Psalms ² The third chapter of Masechess Moed Kattan

After three days of mourning, one who teaches Torah to children is permitted to teach the children everything they need to learn, so that they are not interrupted from their studies; for the (study of) children whose mouths are pure of sin, is more precious than the study of adults. Likewise a mourner's young children should not be interrupted from their studies, for they are not obligated to observe mourning.

Even if the mourner is a Kohein and there is no other Kohein in the synagogue, he is forbidden to go up to read the Torah.

When he prays during all seven days of mourning, a mourner should not recite Pittum Haketoress, Keitsad [How was the incense compounded] nor should he say Maamados, and after the Chapter of Eizehu Mekoman,³ is recited daily. he should not say Yehi Ratzon etc. [May it be Your will] (because a mourner may not send offerings). When reciting Havdalah at the conclusion of Shabbos over a cup [of wine], he should not say the introductary verses of joy, but should begin immediately with the berachos.

footnotes: ³ “Where are the offerings slaughtered.” This chapter of Mishnayos

During his seven days of mourning a mourner should not officiate as Chazzan unless there is no one else to lead the prayers. But if he is in mourning for his father or mother, the custom is to permit him to be the Chazzan even if there is someone else capable of doing so. It is customary that a mourner not be the Chazzan on Shabbos and Yom Tov⁴ and Kail Erech Appaim are not said, a mourner should not be the Chazzan, except on the day before Yom Kippur. Biur Halachah 132. On Rosh Chodesh he may be the Chazzan for Shacharis, provided someone else continues with the Hallel. However, the Chayei Adam says that the Gra did not allow a mourner to be the Chazzan at Shacharis on Rosh Chodesh. Mishna Berurah 581:7. A mourner should not be the Chazzan at Shacharis on Chanukah. Mishna Berurah 683:1 A mourner is allowed to be Chazzan at Mincha and Ma’ariv on Chanukah. But not on Chol Hamoed. Mishna Berurah 671:44—Peri Megadim. during his entire year⁵ 581:7. [of mourning] unless there is no one else to do so.⁶ as accurately as he, he should read it for everyone. Mishnah Berurah 696:12. If he was accustomed to be the Chazzan even before he became a mourner, he is permitted to do so in any event. See Chapter 128:8 above.

footnotes: ⁴ On days when Lamanetzaiach ⁵ If he is mourning the loss of a parent, or thirty days if he is mourning the loss of another relative. Mishnah Berurah ⁶ If no one else can read the Megillah

What is the rule concerning the exchange of greetings? During the first three days, a mourner must not greet anyone. If others who are unaware that he is a mourner greet him, he should not return the greeting, but should inform them that he is a mourner. From the third day until the seventh day, he must not greet anyone, but if others who unaware that he is a mourner greet him, he may respond to their greetings. From the seventh until the thirtieth day, he may extend greetings to others for they have peace of mind, but others should not greet him because he lacks peace of mind. If they did not know he is a mourner and they greeted him, he may respond to their greetings. After thirty days, he may exchange greetings like anyone else.

Since he is forbidden to greet anybody, he is certainly forbidden to laugh. Therefore, during the seven days of mourning, he must not take a child in his arms, so he should not be induced to laughter. He is also forbidden to engage in lengthy conversation with people.⁷ 384:9 writes, “It is obviously forbidden for a mourner to read secular books and certainly newspapers.” However, if he does so out of respect for a group of people, as when many come together to console him, he is permitted to say (when they are leaving), "Go to your homes in peace," for out of respect for a group of people, it is permitted.

footnotes: ⁷ Aruch HaShulchan

In a place where it is customary to greet the mourners on Shabbos, you may do so. The mourner may greet everybody on Shabbos since it is done publicly.

He is permitted to say the berachah, Shehecheyanu even during the seven days of mourning, when it is necessary, for instance on Chanukah, or when eating a new fruit and the like.