Leviticus can also be called “The Book of the Law of the Priests” as it contains very little historical matter, concerning itself with priestly legislation and the practice of the Law among the people. Much importance is placed upon Israel’s separation from all heathen influences so that the nation may retain its religious purity.

Leviticus 11

11:44 For I am the LORD your God: ye shall therefore sanctify yourselves, and ye shall be holy; for I am holy: neither shall ye defile yourselves with any manner of creeping thing that creepeth upon the earth.