The distinction between clean and unclean is a significant theme in the Bible, particularly in the Old Testament, where it is closely associated with the laws given to the Israelites. This distinction is primarily found in the books of Leviticus and Deuteronomy, where God provides detailed instructions on what is considered clean and unclean in various aspects of life, including food, animals, diseases, and bodily conditions.

Clean and Unclean Animals

The dietary laws in Leviticus 11 and Deuteronomy 14 outline which animals are clean and may be eaten and which are unclean and must be avoided. Clean animals typically include those that have a divided hoof and chew the cud, such as cattle, sheep, and goats. In contrast, animals like pigs and camels are deemed unclean. Among aquatic creatures, only those with fins and scales are considered clean. Birds of prey and scavengers are listed as unclean, while certain insects, like locusts, are clean.

Leviticus 11:46-47 states, "This is the law regarding animals, birds, all living creatures that move in the water, and all creatures that crawl along the ground. You must distinguish between the clean and the unclean, between the living creatures that may be eaten and those that may not be eaten."

Clean and Unclean Conditions

The laws also address various conditions that render a person unclean, such as skin diseases (often translated as "leprosy"), bodily discharges, and contact with dead bodies. Leviticus 13-15 provides detailed instructions on diagnosing and managing these conditions, emphasizing the need for purification rituals to restore cleanliness.

For example, Leviticus 15:31 instructs, "You must keep the Israelites separate from things that make them unclean, so they will not die in their uncleanness for defiling My dwelling place, which is among them."

Ritual Purity and Worship

The concept of clean and unclean is closely tied to the Israelites' ability to participate in worship and community life. Being in a state of uncleanness often required temporary separation from the community and the performance of specific rituals to regain cleanliness. This separation underscores the holiness required to approach God, as seen in Leviticus 20:25-26 : "You are therefore to distinguish between clean and unclean animals and birds. Do not defile yourselves by any animal or bird or anything that crawls along the ground—those which I have set apart as unclean for you. You are to be holy to Me because I, the LORD, am holy, and I have set you apart from the nations to be My own."

New Testament Perspective

In the New Testament, the distinction between clean and unclean is revisited, particularly in the context of the early Church's expansion to include Gentiles. Jesus challenges traditional views on purity, emphasizing the importance of inner purity over external observance. In Mark 7:18-19 , Jesus declares, "Are you still so dull? He asked. Do you not understand? Nothing that enters a man from the outside can defile him, because it does not enter his heart, but it goes into the stomach and then is eliminated." Thus, He declared all foods clean.

The Apostle Peter's vision in Acts 10 further illustrates the shift in understanding, as God reveals that what He has made clean should not be called unclean, symbolizing the inclusion of Gentiles into the faith. This vision is recounted in Acts 10:15 : "The voice spoke to him a second time: 'Do not call anything impure that God has made clean.'"

Theological Significance

The distinction between clean and unclean serves as a tangible expression of the call to holiness and separation from sin. It reflects the broader biblical theme of God's people being set apart for His purposes. While the specific dietary and ritual laws are not binding on Christians today, the underlying principles of holiness, purity, and obedience to God remain central to the faith.