It is permitted to say Tehillim on the night of the sixth day (the eve of Friday [i.e., Thursday night]), and on the nights of Shabbat and Yamim Tovim.
Sources and Explanations
The Ben Ish Chai (Pekudei, ot 7) writes: “On the night of Shabbat and the night of Yom Tov one may read Mikra (Scripture), and there is no concern; likewise, on the night of the sixth day one reads twenty-six pesukim (verses), and there is no concern.” In Rav Pe’alim (Orach Chaim, vol. 2, she’elah 2) he also wrote in the name of the Chida that he would say Tehillim on the night of Shabbat, and he added that Yom Tov is also included in this. Similarly, the Me’asef Lechol HaMachanot (Orach Chaim, siman 1, ot 38) cited, in the name of Sefer Kumi Roni, quoting the Arizal, that the sixth day prepares for Shabbat, and then Divine mercy is aroused on it; therefore one may read Mikra on its night. The Chida, in his book Yosef Ometz (siman 54), cited Sefer Sha’ar HaMitzvot as being lenient, because the night of the sixth day prepares for holy Shabbat and Divine mercy is aroused on it, and all the more so one should be lenient on the nights of Shabbat itself. Rabbi Chaim Palagi (in the introduction to his book HaKatuv LeChaim on Tehillim, s.v. “Venafshi Yesovev”) cited the words of the Emet LeYaakov that on the nights of the sixth day and of Shabbat there is no objection to reading before midnight (chatzot). Likewise, the sefer Yesod VeShoresh HaAvodah (Sha’ar HaShishi, Sha’ar HaNitzotz, chapter 2) was lenient: after writing that it is permitted to read Mikra at night if one studies the commentary along with the reading, he explained that on the night of the sixth day and on the night of holy Shabbat one need not do so, and may read without the commentary.
Regarding the nights of Yamim Tovim, Rabbi Betzalel Stern, in Responsa Betzel HaChochmah (vol. 4, siman 44, ot 6), proved from Masechet Soferim (chapter 14, mishnah 18) that they too are included in the permission, and likewise from the fact that the custom was to say Shir HaShirim on the night of the second day of Yom Tov of the Diaspora of the last days of Pesach, and on the night of the second day of Yom Tov of Atzeret (Shavuot) they read the book of Rut.
His brother, Rabbi Moshe Stern, in Be’er Moshe (vol. 4, siman 22, ot 2), raised a difficulty from the Mishnah (Yoma 18b) that on the night of Yom Kippur they would read pesukim from Tanach to the Kohen Gadol so that he would not fall asleep; and he resolved it based on what we wrote above, that since the sixth day prepares for Shabbat one may read then, and so too here.
From the sefer “Shaf Veyativ – Laws of Saying Tehillim” by Rabbi Shay Tahan, Chapter 2: The Proper Times for Saying Tehillim, Halacha 13 (p. 23 in the print edition). Translated from the Hebrew original.
