two young pigeons brought to a priest, one for a sin offering and the other for a burnt offering, on the eighth day. According to textual criticism, the writing style, vocabulary, and so forth, is also indicative of a single author for the two chapters. Consequently, most biblical critics view Leviticus 12 as originally belonging immediately after Leviticus 15:30, as Leviticus 15 has the structure of discussion on male non-sexual discharges, followed by discussion on male sexual discharges (semen), followed by discussion on female non-sexual discharges, and thus Leviticus 12 completes the pattern, as it discusses childbirth, which can be viewed as sexually connected (conception) discharge (of a baby) by a female. Although there is not complete agreement about why this Chapter was moved, the currently most prominent reason given is that, at a later point in time, the view of childbirth changed, and it was no longer viewed as a sexual discharge. Modifications According to critical scholarship, the entire Priestly Code is a later addition, within the Priestly Source, to the earlier Holiness Code. However, textual criticism indicates it as having several different authors, some of whom appear, according to textual critics, not only to have added laws, but to have added modifications onto earlier ones within the Code. Progression to naturalism Some of the ritual laws, or at least portions of these laws, involve two similar animals being brought to the priest, one being killed in a certain manner, and its blood sprinkled onto the sinner, the other being sent away. Such rituals involve the idea that sin can be transferred, from the sinner to the living animal, via the blood of its dead associate. These are generally considered to be amongst the oldest layer of laws, since they invoke extended supernatural ideas, rather than simply involving belief in a god. Other ritual laws also involve an animal being sacrificed, and its blood again being passed onto the sinner, but this time as a symbol that the sinner has paid for their sin, and is now forgiven their sin. These laws involve the idea that sin is something to be atoned for rather than taken away. In anthropology generally, as well as in biblical criticism, this is viewed as a later development, replacing conceptions of the supernatural with simply being fined for the sin. Nevertheless, these laws are still viewed as indicating gradual progression from the earlier layer,