"This chapter contains a selected list of creatures that divides each type of creature into various classes of purity. According to the final verse in the chapter, the decisive question was whether a class of animals was unclean or clean. The goal of the distinctions was to determine whether an animal could be eaten. The notion of uncleanness and cleanness is specifically applied in this chapter to the question of holiness. Violating any of the regulations relating to clean and unclean animals rendered one unclean (i.e., profane or common, 11:44-45), and thus unable to enter into community worship (12:4). The purpose of the chapter is to tie the concept of holiness to God's own example of holiness (11:45)."101
Uncleanness was not all the same under the Old Covenant; there were degrees of uncleanness. The uncleanness that certain defiling things caused required simple purification, for example, washing and waiting a short time. The uncleanness that other defiling things caused required more involved rites.
The reason or reasons for the distinction between a clean and an unclean animal are still somewhat unclear. Even the identity of some of the animals is obscure.102
"Many attempts have been made by scholars and expositors over the centuries to interpret the catalogue of abominable creatures in the book of Leviticus, but with uncertain results."103
Many ancient nations and religions observed lists of clean and unclean foods. These lists differed from one another but undoubtedly had their origin in the clean unclean distinction that God specified at the Flood (cf. Gen. 7:2-3). The presence of this distinction in the ancient Near East points to a common recognition of the inadvisability of eating certain foods. This recognition shows that the Fall has affected the whole creation, not just humankind (Rom. 8:19-22).
There have been at least six major different explanations for the distinction between clean and unclean animals in the Mosaic Law.104Some of these views have very ancient pedigrees.
1. The distinction is arbitrary. The rationale was known only to God. God simply told the Israelites what to do to test their obedience (cf. Gen. 2:16-17). They had no idea what the reasons for these distinctions were.105The problem with this approach is that it is negative; it offers no explanation that human beings can understand.
2. The distinction is cultic. The reason the Israelites where to regard some animals as unclean was that the pagans used them in their worship and or associated them with their deities. Avoidance of these unclean animals then was a mark of the Israelites' fidelity to the Mosaic Covenant.106The problem with this view is that it explains very little of the evidence. The Israelites may have associated certain unclean animals with pagan cultic practices, but scholars have not been able to explain all the prohibitions on this basis alone.
3. The distinction is hygienic. Those who hold this view believe that the unclean animals were unfit to eat because they carried diseases or were unhealthful.107This view has gained popularity in recent times as many readers have become increasingly concerned about health care and medical science.108
"In general it can be said that the laws protected Israel from bad diet, dangerous vermin, and communicable diseases. Only in very recent days have better laws of health been possible with the advance of medicine. These were rule-of-thumb laws that God gave in his wisdom to a people who could not know the reason for the provision."109
There are good reasons, however, for believing that the Israelites did not view these provisions as hygienic. First, hygiene can explain only some of the distinctions. Second, there is no hint in the Old Testament that God regarded the animals He proscribed as dangerous to health. Third, this view fails to explain why God did not forbid poisonous plants as well as dangerous animals. Fourth, if these animals were dangerous to eat, why did Jesus Christ pronounce them good later (Mark 7:19)?
4. The distinction is symbolical. This view sees the behavior and habits of the clean animals as illustrating how the Israelites were to behave. The unclean animals represented sinful people.110Some commentators have adopted this view but have applied the criterion subjectively, without careful regard to the text of the whole Mosaic Law. However when one views the data in the Mosaic Law comprehensively and seeks to understand the distinctions on that basis, this view seems to make the most sense.
5. The distinction is aesthetic, based on the animal's appearance.111This view seems entirely subjective.
6. The distinction is ethical. The animals chosen taught reverence for life.112This view also seems highly subjective and impossible to prove.113
Probably a combination of these reasons is best. The basic idea underlying holiness and cleanness seems to have been wholeness and normalcy.114God seems to have regarded imperfection or abnormality in the animal world as unclean.
"Holiness requires that individuals shall conform to the class to which they belong."115
This does not explain all the cases, however. For example, why did God declare sheep and goats clean but pigs and camels unclean? One explanation is that sheep and goats conform to the norms of behavior that are typical of pastoral animals (chewing their cud and or having cloven feet). Pigs and camels do not.116
"Further analysis demonstrates that each sphere of the animal realm is similarly structured. Water creatures divide into the clean and the unclean, but land and air creatures further subdivide into clean animals that may be eaten and clean animals that may be sacrificed as well as eaten. This threefold division of animals--unclean, clean, and sacrificial--parallels the divisions of mankind, the unclean, i.e., those excluded from the camp of Israel, the clean, i.e., the majority of ordinary Israelites, and those who offer sacrifice, i.e., the priests. This tripartite division of both the animal world and the human realm is no coincidence, as is demonstrated by various laws in the Pentateuch, which apply similar principles to man and beast (Gen. 1:29-30; Exod. 13:2, 13; 20:10; 21:28ff.; 22:28-29 [Eng. 29-30]; Lev. 26:22). Once it is admitted that the animals symbolize the human world, the uncleanness of the birds of prey becomes intelligible: they are detestable because they eat carrion and flesh from which the blood has not been drained properly, acts that make men unclean (Lev. 11:13-19; cf. 11:40 and 17:10ff.)."117
As late as New Testament times the Jews appear to have regarded their food laws as symbolic of the division between themselves and Gentiles. The abolition of these laws under the New Covenant illustrates the fact that Christ has broken down the wall of partition that separated Jews and Gentiles for so long.