Today we celebrate the Nativity of the Blessed Virgin Mary! My missal explains it well:
At the time of Mary's birth the whole world was plunged in darkness. The heathen nations were steeped in vice and pride. The Jews, beloved of God, had strayed from Him. Everywhere there was sin and gloom, no bright spot on the face of the earth. But when Mary was born a light arose amid the darkness: the dawn of the glorious day that was to usher in the Redeemer. So, too, the darkness of the sinner's soul is dispersed by Mary's holy influence. Where the love of her is born in the soul, all becomes full of light, and Jesus comes to make His habitation there. Mary, in the first hour of her life, brought more glory to God than all the Saints of the Old Testament. In her were made perfect the obedience of Abraham, the chastity of Joseph, the patience of Job, the meekness of Moses, the prudence of Josue. It is because she is the model and pattern of these and all other virtues that she can communicate them to us.
Father gave the most beautiful sermon on Our Lady today. He spoke of many things - how her birth was the beginning of our Redemption, how she is pivotal to the plan for mankind's Salvation, how she is a source of graces, an intercessor like no other, a visitor from heaven appearing on earth when her Son wills it, model of all virtues, mediator at the hour of death. He mentioned how Mother Church pays her liturgical honor with so very many feast days dedicated to Our Lady throughout the year, along with every Saturday not assigned to another saint's feast. He spoke of how sad it is that in spite of all this, many Catholics today have little or no devotion to her, do not call upon daily, do not pray her rosary, do not thank her for her love and constant care, do not take advantage of this wellspring of motherly love and graces and blessings. He referred to that moment when Our Lord presented Our Lady to John as He hung upon the cross (John 19:26,27), declaring him to be her son and her to be his mother, and a mother for all of us for all eternity as well. Did this not show how important it is for us to remain ever close and devoted to His mother? Would He have done so otherwise?
Thy Nativity, O Virgin Mother of God, was the herald of joy to the whole world: since from thee arose the Sun of Justice, Christ our God, who, destroying the curse, bestowed the blessing, and, confounding death, brought us the gift of life everlasting. - Antiphon at the Magnificat, Nativity of the Blessed Virgin Mary
It is with great joy that we honor Our Lady on this day of her birth! (Michael tells me that when Eliza went up to pray at the Blessed Mother's altar as she does after every Mass she whispered 'Happy Birthday'. She knows!)