Vayikra starts the third book of the Torah, called Torah Kohanim, the priestly code.
While the books of Bereshit (Genesis) and Shemot (Exodus) emphasize the legendary and historical background of the Jewish people, Vayikra is primarily legislative; outlining the laws governing the practices of an ancient (Israelite) people and their religion.
"Ye shall be holy for I, the Lord your God am holy," permeates the portions of Vayikra and serves as the basis for the unique idea of the holiness of man. This code of holiness is paramount to the idea of a free and moral Jewish life. The code of holiness attempts to liberate us from our animal like characteristics and make us more human in our behavior. It is our compass to a quality daily human life.
Vayikra occupies the middle portion of the Chumash. It represents the heart and core of our Torah, for it embraces the rituals, laws, and commandments by which we, the Jewish people were to become "a kingdom of priests and a holy nation."
The portion of Vayikra deals almost immediately with ritual animal sacrifice and the priestly responsibilities involved with the sacrifices. The animals contributed to the congregational sacrifices, are offered in our stead, as atonement for our sins. All of this is to teach us that the true measure of a person's worth is not found in the material riches he/she may possess, nor in the size of his/her monetary contributions to worthwhile causes. It is rather to be found in his/her personal qualities, his/her character, and contributions of self to the service of God and to our fellowman.
Rabbi Gabe Elias