The hymns we hear during Advent are one of the season's greatest consolations. And is there any musical composition quite as evocative as the beautiful blend of "What Child Is This?" and the more recently written, "Child of the Poor"? The arrangement, designed to alternate verses of the two songs, makes a powerful and haunting meditation on the meaning of the birth of Jesus. It helps us understand that the Incarnation is more than a story told once, but the ongoing tale of God's life in the world, particularly among those on the margins. "What Child Is This?" is an old hymn. It was written by William Chatterton Dix in the year 1865. Unlike most hymns and carols, it doesn't…