As mentioned, Leviticus contains revelation that was particularly appropriate for the priests. While ritual and legal matters predominate, Moses wove them into the historical narratives so as one reads Exodus, Leviticus, and Numbers in order there is chronological movement forward. As we shall see, the legislation appears in the narrative at significant and reasonable places.
"The content of Leviticus supplements and completes that of Exodus in the religious and social spheres--and particularly the religious and ritual aspects of the covenant as made, broken and renewed actually at Sinai; this would be reflected by the terminal blessings and curses of Leviticus 26."4
"Leviticus enlarges upon matters involving the ordering of worship at the divine sanctuary that are mentioned only briefly in Exodus. Whereas the latter described the specifications and construction of the tabernacle, Leviticus narrates the way in which the priests are to care for the sanctuary and throne room of the Great King. The work is a fundamentally important legal treatise because it contains the regulations by which the religious and civil life of the Hebrew nation was to be governed once the land of Canaan was occupied."5
Historically the book fits within the one month between God's occupation of the tabernacle (Exod. 40:17, 34-38) and the taking of the census at Sinai (Num. 1:1-3). However because it contains so much legal material, we should consider it along with the rest of the Mosaic Law that God began to reveal in Exodus.
"It carries on to its completion the giving of the law at Sinai, which commenced at Ex. 25, and by which the covenant constitution was firmly established."6