It is permitted to recite Tehillim at night by way of supplication and prayer.
Sources and Explanations
In the sefer Yad Yehudah (siman 22) he writes that it is permitted to recite [Tehillim] at night by way of prayer and supplication in a time of communal distress, since this is not a matter of study; and several mizmorim are said in the Shema recited at bedtime, and the custom of the Sephardim is to say three mizmorim of Tehillim after Arvit: “LaHashem ha’aretz umelo’ah,” “Lamenatze’ach al hagittit,” and “Havu laHashem benei eilim.”
See the sefer Chazon Ovadia (Avelut, vol. 1, p. 19), and it is brought in the sefer Orchot Maran (vol. 2, p. 854) that this is how Rabbi Ovadia Yosef would instruct the members of his household when one of the household was ill. See further in the sefer Alenu Leshabe’ach (vol. 2, pp. 631–632). And so too writes Responsa Vayechi Ya’akov (Orach Chaim, siman 9).
From the sefer “Shaf Veyativ – Laws of Saying Tehillim” by Rabbi Shay Tahan, Chapter 2: The Proper Times for Saying Tehillim, Halacha 11 (p. 22 in the print edition). Translated from the Hebrew original.
