A mourner should not recite Tehillim during the seven days of his mourning, except for those pesukim (verses) that he reads in the order of the tefillah, and chapters that do not bring one to joy. However, a mourner who does not know how to study the matters permitted to a mourner may read chapters of Tehillim.
Sources and Explanations
The Shulchan Aruch (siman 384) states that a mourner is forbidden in Torah study, but he is permitted to read Iyov, Kinot, the calamitous passages in Yirmiyahu, and the laws of mourning. Now, one must investigate whether the intent is that he is completely exempt from the mitzvah of Torah study, and they merely permitted him, if he wishes, to engage in the calamitous passages; or perhaps he is obligated to study, since mourning, which is rabbinic, does not override the Torah mitzvah of Torah study, and he simply should not engage in matters that bring joy.
See Chazon Ovadia (Avelut vol. 2, p. 190), where Rabbi Ovadia Yosef cites a dispute regarding whether a mourner is obligated in the mitzvah of Torah study. In Sefer Shevet Yehudah (siman 384) he writes: “That the mourner is completely exempt from Torah study and is not obligated to study even the calamitous passages, but if he wishes to study the calamitous passages he may.” Sefer Misgeret HaShulchan (Yoreh De’ah 384:4) agreed with his words, and so it is in Erech HaShulchan (554:1) regarding Tishah Be’Av; but he contradicted his position regarding a mourner (Kuntres Acharon, siman 554), where he noted that from the words of the Chacham Tzvi (siman 100) it is evident that a mourner must study the calamitous passages, and it is not optional. Rabbi Chaim Palagi disagreed with this in his book Moed Lechol Chai (siman 10, ot 21), holding that he is obligated in Torah study.
Now we must discuss whether reciting Tehillim is considered Torah study of a joyful matter, which is forbidden to a mourner. In Leket Yosher (Orach Chaim p. 112) he writes that the Terumat HaDeshen said his regular portion of Tehillim also during the days of his mourning. Likewise, the Pri Megadim (siman 584, Eshel Avraham 1) writes that a mourner is permitted to read by way of supplication.
From the sefer “Shaf Veyativ – Laws of Saying Tehillim” by Rabbi Shay Tahan, Chapter 10: Saying Tehillim During Mourning, Halacha 3 (p. 150 in the print edition). Translated from the Hebrew original.
