This initial B, introducing the first psalm, Beatus vir, represents King David who is shown here playing a psaltery, a stringed instrument consisting of a shallow box that is plucked, instead of his more traditional harp. The psaltery was widely popular in Europe during the 14th and 15th centuries. The illuminator of this striking initial is named after his earliest dated work, an illuminated volume of Suetonius’s Vitae Imperatorum (Lives of the Emperors), which he decorated in 1431 for Filippo Maria Visconti, Duke of Milan (1412–47). He is noteworthy for his distinctive use of line and color.