Leviticus 12:1–8 gives details regarding purification following childbirth. With the birth of any child, there is typically a large loss of blood. Since blood is associated with life (Genesis 9:4; Leviticus 17:14), the loss of blood correlates with the loss of life, rendering one unfit to be in the presence of God (who is fullness of life, John 1:3–4). Coming as part of the clean/unclean laws (Leviticus 11:1 - 16:34), the focus of purification is not atoning for sin but dealing with the pollution that comes from living in a fallen world.1 Though Leviticus 12:1–8 refers only to women, reference is made to Mary and Joseph (they) most likely because Joseph helped with the delivery.2
22 And when the time came for their purification according to the Law of Moses, they brought him up to Jerusalem to present him to the Lord