ON THE COVER: A contemplative King David seems engrossed in composing a psalm, in a tapestry by Israeli artist Shraga Weil (b. 1918). Nearly half of the Psalms—73 of 150, in the Hebrew version—are credited to ancient Israel’s warrior-king. Nahum M. Sarna explores this cherished collection of poetry, which informs both Jewish and Christian worship, in “Songs of the Heart—Understanding the Book of Psalms.”