It is well known that Dawid HaMelekh was the soul of all Israel, as written "The praise of Hashem shall my mouth speak and all flesh shall bless His Holy Name." The reason it says the words "all flesh" is meaning at any time (Yismah Yisrael, Parashat Eqeb). Meaning whenever one is in need, he should pray Tehilim. The Semah Sedeq once said that if we knew the strength of the Tehilim, and the Heavens we would recite it every moment.Their actions make kindness and mercy (ibid.). The Emeq HaMelekh writes (pg. 15) that the book of Tehilim declines many stumbling blocks and some damages from him and his household members, and his family as well. It makes great blessings goodness and merits to him. It is also interesting that the Magen U'Shemesh writes that Gimatria of the one hundred and fifty Pesuqim is corresponding to the Gimatria of Pidion (redemption).
The Midrash in Pinhas writes that whatever a person needs, he should recite Tehilim for it. (He should recite it consecutively) and not stop for the Yehi Rason between the books of Tehilim, until he has completed the entire Sefer. Through the Tehilim we bring closer the redemption (Midrash Tehilim, Shir HaShirim). "Whoever recites Tehilim every day, it is as if we fulfilled the entire Torah (Rabenu Efraim, Parashat WeZot HaBerakha)." One who wants to have a connection with Hashem, should recite Tehilim (Shala, Nazir 257). The Noam Elimelekh writes that Tehilim have the possibility to make drastic changes and there is no Sat-an or obstacle stopping them. The Shebut Ya'aqob writes (Heleq Bet, Yoreh De'ah 44) that if one desires to make many prayers, he should recite Tehilim, because it is leaning Torah, and there are many good omens in it. Rabbi Haim Palagi writes (Minhagi HaHabi"f 80) that one who recites Tehilim (and Brikat HaMazon) daily lengthen their years and days. Rabbi Haim Palagi also writes that this worlds stands upon Tehilim, and one redeems themselves from any damages and redemption will come through the recitation of Tehilim (Haqdama, Kol HaKatub LeHaim). One who recites Tehilim daily merits to be under the Kise HaKabod (Chair of Honor). We have nothing greater than Tehilim because contains everything (Shala).
There are countless compliments and praises of the sacred and holy book of Tehilim, and one could go on and on upon its' praise, so always remember, we can save many people from sickness or anything bad by just reciting Tehilim!