Rorate caeli desuper, et nubes pluant justum. (Is. 45:8), Drop down dew, ye heavens, from above, and let the clouds rain down the Just One. Thus begins the Introit for the Mass of Our Lady on Saturday during Advent. Come and join us at St. John's in North Park and hear the expectation for the coming Messiah in the ancient Gregorian chants of the Traditional Latin Mass.