When one sins, he is heavy because of his selfishness. He can neither read nor pray because praying and kneeling seem daunting. Since then, you cannot pray, nor keep vigil, at least force yourself to study the Psalms. The Psalms express prayer, repentance, praise, thanksgiving, and contain feelings and experiences that can raise even the weakest man. Just like, when the other loses his senses, you give him a bit of raki, and you revive him, precisely so, read the Psalms, and they will resurrect you again.(Elder Aimilianos)