On the Wednesday of Ember week in Advent, the Mystery of the Annunciation is commemorated by many Churches. The Mass is sung early in the morning, and the Church is illuminated, as a token that the world was still in darkness when the Light of the world appeared. The Mass is sometimes called the Golden Mass, possibly because in the Middle Ages, the whole of the Mass, or at least the initial letters, were written in gold — or on account of the golden magnificence of the solemnity and the special, great, ‘golden’ grace which, at that time, is obtained by numerous prayers. It is also called the Rorate Mass after the first words of the Introit of the Mass, Rorate Cœli: