After the circumcision of the boy, the mother underwent a second period of purification. During this time, she was no longer ceremonially unclean, but she was not ceremonially clean either. These thirty-three days served as an interval between ceremonial uncleanness and ceremonial cleanness. The Israelite woman was not allowed in the sanctuary.
4 Then she shall continue for thirty-three days in the blood of her purifying. She shall not touch anything holy, nor come into the sanctuary, until the days of her purifying are completed.