The Book of Leviticus:
The setting is at Mt Sinai and the time is after the exodus from Egypt, just before starting the journey to the promised land, approx one year.
This book records the different offerings the Priests performed in the Tabernacle in the service to God. Also Aaron's priesthood is established and important rituals described, namely clean and unclean food, the Day of Atonement and Holy Days.
Other items of note are: Jubilee years, blessing and cursings, vows and tithes.