Its setting is Mount Sinai
Leviticus opens with the LORD speaking to Moses from the newly established tabernacle, the tent where God met with Israel (Leviticus 1:1). The book closes by locating its commands at Mount Sinai (Leviticus 27:34). So, whatever questions people have about the book's later copying or collecting, Leviticus itself places the events and instructions in Israel's wilderness years after the exodus from Egypt.
Exodus says the tabernacle was set up on the first day of Israel's second year after leaving Egypt (Exodus 40:17). Numbers then begins on the first day of the following month, while Israel is still in the Sinai wilderness (Numbers 1:1). Read in the flow of the Torah, Leviticus belongs in that period between those scenes. It is a book for a people learning how to live near a holy God.
And the Lord called unto Moses, and spake unto him out of the tabernacle of the congregation, saying,
Did Moses write it?
Many Jews and Christians have traditionally understood Moses to be the writer of Leviticus, along with the other first five books of the Bible. Jesus spoke of Moses writing about him and treated Moses' writings as authoritative (John 5:46-47). Leviticus repeatedly records God speaking directly to Moses, which fits that longstanding view.
Still, Leviticus does not contain a sentence saying, “Moses completed this whole book on this particular day.” Scripture shows Moses writing down God's words in the wilderness (Exodus 24:4), but it does not supply a modern-style publication date for Leviticus. That means it is wise to distinguish what the text clearly says from details it leaves unstated.
These are the commandments, which the Lord commanded Moses for the children of Israel in mount Sinai.
Why dates vary
People who date the exodus earlier often place these Sinai events in the fifteenth century BC. Others date the exodus later and place them in the thirteenth century BC. Those conclusions depend on how readers connect biblical chronology with ancient history, rather than on a date printed in Leviticus itself.
Some modern scholars also suggest that priests or editors shaped the book into its final form at a later time. Other Christians continue to hold that Moses wrote it during the wilderness journey. Faithful readers may disagree about those historical questions, but the book's own central claim is clear: its worship, sacrifice, purity, and community instructions came from God to Israel through Moses at Sinai (Leviticus 27:34).
Read Leviticus in its purpose
An exact writing date matters less than the question Leviticus keeps raising: how can a sinful people draw near to a holy God? Its sacrifices and priesthood show that approach to God is not casual. The New Testament connects those themes to Jesus, who offered himself once for sin (Hebrews 10:10).
So read Leviticus as a real book rooted in Israel's Sinai journey, not as a random collection of rules. Notice how often God makes a way for his people to be cleansed, forgiven, and restored. That thread helps make sense of both Leviticus and the rest of the Bible.
By the which will we are sanctified through the offering of the body of Jesus Christ once for all.