SHORT ANSWER
The Book of Leviticus is a challenge for many as they begin reading the bible cover to cover. It reads like a manual because that is what it is! Written by Moses about 1300 BC, it was designed to be a handbook for the priests or Levites, hence the name Leviticus. It sets down the regulations that were to govern the life of Israel in general and specifically to give regulations concerning sacrifice and worship.
All of the major sacrifices are described, as well as the way they were to be offered. We have the following Offerings:
Burnt Offering - Voluntary act of worship; atonement for unintentional sin in general; expression of devotion, commitment and surrender to God. Bull, ram or male bird is offered - wholly consumed no defect.
Grain Offering - Voluntary act of worship; recognition of God's goodness and provisions; devotion to God. Grain, fine flower, olive oil, incense, baked bread, salt offered - accompanied burnt and fellowship offering.
Fellowship Offering - Voluntary act of worship; thanksgiving and fellowship as it included a communal meal. Any animal without defect from herd or flock offered.
Sin Offering - Mandatory atonement for specific unintentional sin; confession of sin; forgiveness of sin; cleansing from defilement. Young bull for high priest & congregation offered. Male goat for leader. Female goat or lamb for common person. Dove or pigeon for the poor. Tenth of an ephah of fine flower for the very poor.
Guilt Offering - Mandatory atonement for unintentional sin requiring restitution; cleansing from defilement; make restitution; pay 20% fine. Ram or lamb offered.
We also have major festivals and holidays discussed as well as special sections devoted to the priesthood and regulations concerning ceremonial matters.
LONG ANSWER
Why read Leviticus as a Christian today? If you were to ask many Christians about Leviticus today, they will possibly recall it as a difficult book devoted primarily to the proper and gruesome management of sin through animal sacrifice. Included are mind-numbing instructions on how to rightly handle infectious skin disease and mildew, and a mishmash of other commandments about not mixing fibers and seeds and not sleeping with your stepmother or sister or nephew—commandments deemed either irrelevant or plain common sense. Leviticus is a very tough book for modern Christians to read, understand and glean an application for their lives.
It is however a very important book. For example, the second greatest commandment, "Love your neighbor as yourself," comes from Leviticus:
Leviticus 19:18 (New International Version)
18 Do not seek revenge or bear a grudge against one of your people, but love your neighbor as yourself. I am the LORD.
Luke 10:26-28 (New International Version)
26 "What is written in the Law?" he replied. "How do you read it?"
27 He answered: "Love the Lord your God with all your heart and with all your soul and with all your strength and with all your mind; and, Love your neighbor as yourself."
28 "You have answered correctly," Jesus replied. "Do this and you will live."
As a Christian, you can't fully comprehend the New Testament and its vocabulary (sacrifice, atonement, holy, unclean, blood) without first understanding Leviticus. You need to approach the book by understanding that the central theme is that God has provided a way for atonement to be made by the offering of sacrificial blood. This whole system found its fulfillment in the shedding of Christ’s blood as the one great sacrifice for the sins of the world. Leviticus also shows that worship is to be orderly and is to follow a regular pattern.
LEVITICUS ECHOES THRU THE BIBLE
The themes of Leviticus echoes many times in the Bible as we can see from the following scripture:
Genesis 4:3-4 (New International Version)
3 In the course of time Cain brought some of the fruits of the soil as an offering to the LORD. 4 But Abel brought fat portions from some of the firstborn of his flock. The LORD looked with favor on Abel and his offering
Genesis 22:13-14 (New International Version)
13 Abraham looked up and there in a thicket he saw a ram caught by its horns. He went over and took the ram and sacrificed it as a burnt offering instead of his son. 14 So Abraham called that place The LORD Will Provide. And to this day it is said, "On the mountain of the LORD it will be provided."
Isaiah 1:11 (New International Version)
11 "The multitude of your sacrifices—what are they to me?" says the LORD.
"I have more than enough of burnt offerings, of rams and the fat of fattened animals; I have no pleasure in the blood of bulls and lambs and goats.”
Isaiah 53:7 (New International Version)
7 He was oppressed and afflicted, yet he did not open his mouth; he was led like a lamb to the slaughter, and as a sheep before her shearers is silent, so he did not open his mouth.
Hebrews 9:24-26 (New International Version)
24 For Christ did not enter a man-made sanctuary that was only a copy of the true one; he entered heaven itself, now to appear for us in God's presence. 25 Nor did he enter heaven to offer himself again and again, the way the high priest enters the Most Holy Place every year with blood that is not his own. 26 Then Christ would have had to suffer many times since the creation of the world. But now he has appeared once for all at the end of the ages to do away with sin by the sacrifice of himself.
Hebrews 13:10-16 (New International Version)
10 We have an altar from which those who minister at the tabernacle have no right to eat.
11 The high priest carries the blood of animals into the Most Holy Place as a sin offering, but the bodies are burned outside the camp. 12 And so Jesus also suffered outside the city gate to make the people holy through his own blood. 13 Let us, then, go to him outside the camp, bearing the disgrace he bore. 14 For here we do not have an enduring city, but we are looking for the city that is to come.
15 Through Jesus, therefore, let us continually offer to God a sacrifice of praise—the fruit of lips that confess his name. 16 And do not forget to do good and to share with others, for with such sacrifices God is pleased.
Ephesians 5:1-2 (New International Version)
1 Be imitators of God, therefore, as dearly loved children 2and live a life of love, just as Christ loved us and gave himself up for us as a fragrant offering and sacrifice to God.
1 John 1:7 (New International Version)
7 But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus, his Son, purifies us from all sin.
Revelation 12:11 (New International Version)
11 They overcame him by the blood of the Lamb and by the word of their testimony; they did not love their lives so much as to shrink from death.
We can see that from the blood of Abel's slain lamb in Genesis, to the robes of the saints washed in the blood in Revelation, the Word of God centers around the blood sacrifice of Jesus Christ.
Hebrews 9:22 (New International Version)
22 In fact, the law requires that nearly everything be cleansed with blood, and without the shedding of blood there is no forgiveness.
Understanding the book of Leviticus; with it’s rites of sacrifice, atonement, concepts of what is holy and what is unclean and most importantly the serious role of blood is critical to understanding the mission of the Christ coming to earth to die for us.
ITS ALL ABOUT JESUS AND HIS BLOOD SACRIFICE
Everything concerning the events of Jesus' life was leading up to the blood being applied in Heaven. Recall that in Leviticus, the blood was to be sprinkled on the mercy seat right after the death of the substitutionary animal of sacrifice. We have Christ as our substitute. He was slain for us upon the Cross, and entered into death for us, and when He arose, He immediately went to heaven, entered into the holy of holies in heaven, sprinkled His precious blood upon the mercy seat before the throne of God, and forever settled the sin questions, and delivered us from the curse of the law. This is clearly taught in the Hebrews:
Hebrews 9:12 (New International Version)
12 He did not enter by means of the blood of goats and calves; but he entered the Most Holy Place once for all by his own blood, having obtained eternal redemption.
God’s grace and love demonstrated by providing the way for his children to be redeemed from sin and death through the atoning death of His Son, Jesus Christ.
John 3:16 (New International Version)
16 For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life.