The Old Calendarists believe that this impoverishes the liturgical and spiritual life of the Church  Greek Independence Day is celebrated on the feast of the Annunciation and 25 March is also a national holiday in the Lebanon. The date is close to the vernal equinox, as Christmas is to the winter solstice; because of this the Annunciation and Christmas were two of the four "quarter days" in medieval and early modern England, which marked the divisions of the fiscal year (the other two were Midsummer Day, or the Nativity of St. John the Baptist, on 24 June, and Michaelmas, the feast day of St. Michael, on 29 September). When the calendar system of Anno Domini was first introduced by Dionysius Exiguus in AD 525, he assigned the beginning of the new year to 25 March, because according to Christian doctrine, the age of grace began with the Incarnation of Christ at the Annunciation, on which date Jesus Christ is believed to have been conceived in the Virgin Mary by the Holy Spirit. Pope John Paul II established March 25 as the International Day of the Unborn Child, for its commemoration of the conception of Jesus.