Today is dedicated to Our Lady! (I love this picture!)
 I will put enmities between thee and the woman, and thy seed and her seed: she shall crush thy head, and thou shalt lie in wait for her heel. [Genesis 3:15] [Latin]
Now the generation of Christ was in this wise. When as his mother Mary was espoused to Joseph, before they came together, she was found with child, of the Holy Ghost.  Whereupon Joseph her husband, being a just man, and not willing publicly to expose her, was minded to put her away privately.  But while he thought on these things, behold the angel of the Lord appeared to him in his sleep, saying: Joseph, son of David, fear not to take unto thee Mary thy wife, for that which is conceived in her, is of the Holy Ghost.
 And she shall bring forth a son: and thou shalt call his name JESUS. For he shall save his people from their sins.  Now all this was done that it might be fulfilled which the Lord spoke by the prophet, saying:  Behold a virgin shall be with child, and bring forth a son, and they shall call his name Emmanuel, which being interpreted is, God with us.  And Joseph rising up from sleep, did as the angel of the Lord had commanded him, and took unto him his wife.  And he knew her not till she brought forth her firstborn son: and he called his name JESUS. [Matthew 1:18-25] [Latin]
 And in the sixth month, the angel Gabriel was sent from God into a city of Galilee, called Nazareth,  To a virgin espoused to a man whose name was Joseph, of the house of David; and the virgin's name was Mary.  And the angel being come in, said unto her: Hail, full of grace, the Lord is with thee: blessed art thou among women.  Who having heard, was troubled at his saying, and thought with herself what manner of salutation this should be.  And the angel said to her: Fear not, Mary, for thou hast found grace with God.  Behold thou shalt conceive in thy womb, and shalt bring forth a son; and thou shalt call his name Jesus.  He shall be great, and shall be called the Son of the most High; and the Lord God shall give unto him the throne of David his father; and he shall reign in the house of Jacob for ever.  And of his kingdom there shall be no end.  And Mary said to the angel: How shall this be done, because I know not man?  And the angel answering, said to her: The Holy Ghost shall come upon thee, and the power of the most High shall overshadow thee. And therefore also the Holy which shall be born of thee shall be called the Son of God.  And behold thy cousin Elizabeth, she also hath conceived a son in her old age; and this is the sixth month with her that is called barren:  Because no word shall be impossible with God.  And Mary said: Behold the handmaid of the Lord; be it done to me according to thy word. And the angel departed from her. [Luke 1:26-38] [Latin]
*** Till she brought forth her firstborn son: From these words Helvidius and other heretics most impiously inferred that the blessed Virgin Mary had other children besides Christ; but St. Jerome shews, by divers examples, that this expression of the Evangelist was a manner of speaking usual among the Hebrews, to denote by the word until, only what is done, without any regard to the future. Thus it is said, Genesis 8. 6 and 7, that Noe sent forth a raven, which went forth, and did not return till the waters were dried up on the earth. That is, did not return any more. Also Isaias 46. 4, God says: I am till you grow old. Who dare infer that God should then cease to be: Also in the first book of Machabees 5. 54, And they went up to mount Sion with joy and gladness, and offered holocausts, because not one of them was slain till they had returned in peace. That is, not one was slain before or after they had returned. God saith to his divine Son: Sit on my right hand till I make thy enemies thy footstool. Shall he sit no longer after his enemies are subdued? Yea and for all eternity. St. Jerome also proves by Scripture examples, that an only begotten son, was also called firstborn, or first begotten: because according to the law, the firstborn males were to be consecrated to God; Sanctify unto me, saith the Lord, every firstborn that openeth the womb among the children of Israel, etc. Ex. 13. 2.