2. she shall be unclean. The notion that the blood of childbirth rendered the parturient ritually impure was widespread in the ancient world, reflected in texts by the Hittites to the north of Israel and by the Greeks to the west. Jacob Milgrom notes that the ancients believed there was seed in the blood discharged by the childbearing woman, and so he proposes that this loss of blood was associated with death and hence conveyed impurity.

as in the days of her menstrual unwellness. The “in” is implied, for what is at issue is not the number of days but the nature of the condition of impurity.

4. thirty days and three she shall stay in her blood purity. The Hebrew, emphasizing the counting, says literally “in thirty days and three days.” When one adds the initial seven days, the total period during which the woman is to avoid contact with consecrated things (and also, evidently, refrain from marital relations) is the formulaic figure of forty days. The blood of the first seven days is considered impure. Afterward, her blood is deemed pure (“her blood purity”) but she must remain in this state for thirty-three days before she is free of the impurity contracted at childbirth.

5. if she bears a female . . . sixty days and six she shall stay. When one adds this number to the initial fourteen days, the total period of sequestration comes to eighty, or twice forty. No entirely satisfactory explanation has been offered for why a female child requires twice the length of time for the mother to be free of impurity, though one suspects a general predisposition of the culture to see the female as a potential source of impurity. Seminal emission also imparts ritual impurity, but the period for ridding oneself of the impurity imparted by menstrual discharge is much longer.

6. an offense offering. The present case is a strategic instance of why it is misleading to render the Hebrew ḥataʾt, as almost all English versions do, as “sin offering.” Surely the childbearing woman has done nothing that can be called a sin. The state of ritual impurity, however, imposed on her by biological circumstances makes her a potential source of violation of the sancta, which would be an offense to the cult and to its divine object, and so she is enjoined to present an offense offering that will mark the completion of her period of purification.

7. the flow of her blood. The literal sense of the Hebrew is “the source of her blood,” the idiom exhibiting a common linguistic pattern in which there is an interchange between cause (“source”) and effect (“flow”).

8. if her hand cannot manage. More literally, “her hand cannot find” (elsewhere, “her hand cannot attain”), with “hand” having its frequent biblical sense of capacity or power.