The angel of the Lord declared unto Mary; and she conceived by the Holy Spirit.” So begins the Angelus, the prayer that celebrates the Annunciation. To the eyes of faith, the coming of Christ was the high point of human history, and so the Church prays the Angelus each day at noon, the high point of the day. Federico Barocci portrays this revolutionary turning point as a serene and graceful moment: The angel Gabriel, who has just alighted, tilts his head toward Mary with a smile of greeting. She in turn raises her hand in mild surprise and calmly sets aside her prayerbook; the angel’s “Be not afraid” seems hardly necessary. < . . .