Before returning to Nazareth three ceremonies were performed relating to Jesus’ birth. They included his circumcision and his presentation in the Temple, concerning which I have written a few words in earlier posts. The third ceremony concerned the ritual of purification that Mary had to undergo according to the Law after the birth of her firstborn. Each ceremony had some significance in Jewish society, and each of the rituals tell a story about human life and how that life relates to God. Luke paints a picture of the birth of Jesus, the Son of God, and how he was introduced into Jewish society, and what that would mean in terms of God’s relationship to mankind.
Mary’s purification ceremony occurred 40 days after the birth of Jesus, her firstborn son (cf. Luke 2:22, 24). The particular sacrifice she offered, namely, two turtledoves, was symbolic of the financial state Mary and Joseph were in at the time of Jesus birth and throughout the following forty days. Some folks have understood this to indicate that Jesus was speaking literally when he claimed he had no place to lay his head (Luke 9:58), but this would be wrong. Moreover, such a teaching could fault Jesus for not supporting his family. The fact remains that, while Jesus was dying on the cross, the Romans tossed lots for his outer garment, because it was so valuable. Who, today, would gamble for the opportunity to claim a homeless man’s clothes? Such a teaching is ridiculous and seeks to glorify the state of the poor rather than pity their plight and help them.
Nevertheless, one might ask: “Why does the Law require a sacrifice for Mary to begin with? What was it about the birth of Jesus that made her ceremonially unclean? Certainly Jesus wasn’t unclean or impure, so how could his birth make Mary impure (cf. Leviticus 12:1-4)? A sacrifice was required, because the birth of Jesus brought about a descent from Mary’s creative prowess, and, therefore, she became ceremonially impure—i.e. just after Jesus’ birth Mary, temporarily, did not possess God’s creative power to bring life into the world. At least for a short time, it had become impossible for her to fulfill God’s command to “be fruitful and multiply and fill the earth” (cf. Genesis 1:28). Although she had not committed any sin by birthing a child, the act of bringing a child into the world had the effect of bringing Mary into a state where she was no longer in sync with God, with respect to her power to create life.
After Jesus’ birth her flow of blood was renewed, and that symbolized death rather than life. The fruit of man’s rebellion in the flow of blood made its presence realized. The whole ceremony is charged with symbolism, pointing not only to the creation life but also its destruction due to sin. While Mary did not sin by becoming a mother, the idea of sin and rebellion is born out in the process of her bringing a newborn into the world and the flow of blood afterward, including the eventual renewal of her monthly cycle in which the loss of blood (Leviticus 17:11) points to the loss of life, i.e. death, the fruit of man’s rebellion.
It is interesting that the rebellion of mankind has its place in the birth of Christ, too. The blessing of peace from God has come, as promised by the angel (Luke 2:14), indicating that he is no longer at war with rebellious mankind. The Savior, Jesus, has come into our world, and he would bring light to mankind and teach us the way of peace (Luke 1:79). The ceremony of purification looked forward to the cross, where God was in Christ reconciling the world to himself (2Corinthians 5:17-19). The rebellion in the race of Adam is undone in the new creation found in Christ.
 I owe this whole idea of birth and death and being unclean to an article written by Chana Weisberg. See “Why the difference in the laws of ritual purity between the birth of males and females?.” Chana Weisberg is the editor of The Jewish Woman website.