Leviticus 12:4

Laws of Purification - Leviticus 12-15 The laws concerning defilement through eating unclean animals, or through contact with those that had died a natural death, are followed by rules relating to defilements proceeding from the human body, in consequence of which persons contaminated by them were excluded for a longer or shorter period from the fellowship of the sanctuary, and sometimes even from intercourse with their fellow-countrymen, and which had to be removed by washing, by significant lustrations, and by expiatory sacrifices. They comprised the uncleanness of a woman in consequence of child-bearing (Lev 12:1-8), leprosy (ch. 13 and 14), and both natural and diseased secretions from the sexual organs of either male or female (emissio seminis and gonorrhaea, also menses and flux: ch. 15); and to these there is added in Num 19:11-22, defilement proceeding from a human corpse. Involuntary emission defiled the man; voluntary emission, in sexual intercourse, both the man and the woman and any clothes upon which it might come, for an entire day, and this defilement was to be removed in the evening by bathing the body, and by washing the clothes, etc. (Lev 15:16-18). Secretions from the sexual organs, whether of a normal kind, such as the menses and those connected with child-birth, or the result of disease, rendered not only the persons affected with them unclean, but even their couches and seats, and any persons who might sit down upon them; and this uncleanness was even communicated to persons who touched those who were diseased, or to anything with which they had come in contact (Lev 15:3-12, Lev 15:19-27). In the case of the menses, the uncleanness lasted seven days (Lev 15:19, Lev 15:24); in that of child-birth, either seven or fourteen days, and then still furthe…

After the laws concerning clean and unclean food come the laws concerning clean and unclean persons; and the first is in this chapter concerning the ceremonial uncleanness of women in child-birth (Lev 12:1-5). And concerning their purification from that uncleanness (Lev 12:6, etc.).

12:4 These thirty-three days are added to the seven previous days (12:2, 3) to yield a total of forty days to complete the mother’s period of purification.