Read: Leviticus 12
The Lord said to Moses, Say to the Israelites: A woman who becomes pregnant and gives birth to a son will be ceremonially unclean for seven days, just as she is unclean during her monthly period. On the eighth day the boy is to be circumcised. Lev 12:1-3
That text certainly reminds us of Mary and Joseph and the baby Jesus. In fact, that Baby came into the world to deal with the very problem which made this chapter necessary. God is not against childbirth, nor against babies. Nor is human birth essentially an inherently unclean event. There is nothing wrong with birth, nor with sex. But these requirements were given to the people of God in order that we might remember a most basic and fundamental fact: that since the fall of Adam every human being born into this world is born into a fallen race.
There is no way by which man in his natural condition is ever going to be able to solve the basic, fundamental problems of human relationships. We are born into a condition that is tainted and twisted. Someone has thrown a monkey wrench into the human machinery, right at the very beginning, and it simply doesn’t operate as God intended. God impresses this upon his people by this restriction, this reminder that something connected with birth is unclean. The fact that a mother was unclean for a week after the birth of a male child (two weeks for a female child), and that she had to go through another thirty-three days of purifying after that, provided an opportunity for her and her whole family to be reminded forcefully that the baby was born with a tainted nature. The circumcision of the male baby was an additional reminder that something needs to be removed from the life inherited from Adam.