The advantage of reciting psalms is exceedingly great. Our Sages have said that King David prayed that one who recited psalms should receive reward for them as one who busies himself with nega’im and ohalos. Therefore, a righteous person should not refrain from studying the entire book of psalms on a weekly basis. Even though the halachic authorities have written that one who is able to study laws and debates and instead busies himself with psalms is considered as one who wastes time from Torah study, nevertheless they did not say this about one who says psalms once a week. There is a time for everything. Especially if they read them together with a group of people, they will ascend in goodwill more than one who busies himself with negaim and ohalos in seclusion.
They also write that one who regularly (recites) the book of psalms pushes away all kinds of punishment and bad afflictions, from himself and the members of his household, from all his family and all the people of his generation. He causes all kinds of abundant blessings, good things and successes to come to them. In the entire world there is nothing as effective to shield a person from harmful influences as saying Kaddish on Psalms. One who wishes to cleave to G-d (may He be blessed) and to his praise, should cleave to the learning of the book of Psalms. There is an accepted tradition from the holy famous men that one who has an immediate problem or difficulty, or he is travelling or crossing the sea or rivers, should read all of the psalms each day without pause, with concentration and subjugation and he will see wonders. This is tried and tested.
All these advantages and many more, were said to a person who reads them as they were fixed, letter by letter, word by word in a joyous and thankful voice and with a low sound. He should give over his spirit to them and understand what he is uttering. They are awesome prayers about enemies of and oppressors of souls. They sing of tyrants and of cutting off all thistles and thorns. They include praise and great tribute to the One whose deeds are awesome. The words are ancient and wonderfully pure of thought, words of a living G-d which were said to King David through divine spirit. Even though we do not have with us one who knows their depth and exaltation, and there are those who do not understand what they are saying at all, even so the words work and bring out fruit up high and the work of our hands should set this up for us as long as he reads them slowly without missing any words and without mistakes as is fitting and appropriate.