THE Book of Psalms contains almost every great religious idea which grew up in Israel. Some of the psalms are epic poetry of the type of the Song of Deborah ( Judges 5) and the Song of Moses at the Red Sea ( Exodus 15). See Psalm 18. There are psalms which express the ethical idealism of the prophets ( Psalm 15). Some psalms express the mood of study and a love of wisdom characteristic of the Book of Proverbs. Other psalms echo the great historical vision with its idea of the role of God as the Guide of human destiny as expressed in Deuteronomy and in the historical books. The Book of Psalms is an epitome of all the nobler religious ideas developed in Israel.
Besides the fact that the Psalms embody the highest ideas of biblical literature they also possess a uniqueness of mood and expression, a spirit which was bound to give them a universal appeal. Although many of the psalms were often understood as describing the vicissitudes of the whole people of Israel, yet they are essentially personal in mood. They describe the inner life, tenderly and vividly. For pure lyrical poetry, for the emotional aspect of the spiritual life, the Psalms are unique in literature. "The Book of Psalms contains the whole music of the heart of man, swept by the hand of his Maker. In it are gathered the lyrical burst of his tenderness, the moan of his penitence, the pathos of his sorrow, the triumph of his victory, the despair of his defeat, the firmness of his confidence, the rapture of his assured hope. In it is presented the anatomy of all parts of the human soul; in it, as Heine says, are collected 'sunrise and sun