Why did God require animal sacrifices in the old testament?

Beloved in Christ, animal sacrifices played a significant role in the lives of the people in the old testament. God himself offered the first animal sacrifice and later established it as part of the law: The Lord God made garments of skin for Adam and his wife, and clothed them (Genesis 3; 21). The garments of skin signifies that a lamb was slain and it's skin was used to cover their nakedness. Later, God instituted the sacrificial system, where sacrifices for sin were offered on a daily and yearly basis.

Why did God require animal sacrifices in the old testament? 

I believe there are two main reasons why God required animal sacrifices. One of the main reason why God required animal sacrifice was to provide temporal forgiveness of sins. As part of the law, when a person sins, he or she must offer a lamb without blemish. The person must then identify with the lamb by laying his hands on the head of the lamb and after that slays the Lamb. The priest uses the blood of the lamb to make atonement for his sins, and God looks upon the sinner with favor and forgives him, see (Leviticus 4; 32-35). Sacrifices for sin were done every single day: Every priest stands daily ministering and offering time after time the same sacrifices, which can never take away sins (Hebrews 10; 11). 

There was the yearly sacrifices for sins as well. This happens once a year on the day of atonement. On that day, the high Priest kills a Lamb and takes it's blood and enters within the veil into the holy of holies and sprinkles the blood on the mercy seat, so that their sins could be forgiven. After, the high Priest lays both of his hands on the head of a live goat and confesses all the iniquities of the children of Israel, and sends it away into the wilderness by the hand of a man who stands in readiness. Symbolically, the live goat bears on itself the sins of the people into a solitary place in the wilderness. The live goat bearing the sins of the people into the wilderness signifies the removal of their sins, see (Leviticus 16). 

The reason why I wrote earlier that those animal sacrifices provided temporal remission for their sins is because, those animal sacrifices could not permanently wash away their sins once for all time, that was why there was a need for those sacrifices to be done daily and on a yearly basis. If those sacrifices could have taken away their sins, there would have been no need for continual sacrifices for sin. The author of Hebrews puts it this way: For the Law, since it has only a shadow of the good things to come and not the very form of things, can never, by the same sacrifices which they offer continually year by year, make perfect those who draw near. Otherwise, would they not have ceased to be offered, because the worshipers, having once been cleansed, would no longer have had consciousness of sins? But in those sacrifices there is a reminder of sins year by year. For it is impossible for the blood of bulls and goats to take away sins (Hebrews 10:1-4). 

The other reason was to foreshadow the substitutionary work of our Lord Jesus Christ. Under the sacrificial system, when a sinner sins, the person must bring forth an innocent lamb, a lamb without spot or wrinkle, and the lamb dies as a substitute for the transgressor. Instead of the sinner to die, the lamb dies in his place. The priest uses the blood of the Lamb to atone for his sins, so the person can experience the joy of having his sins forgiven. God instituted the sacrificial system to paint a picture of the atoning work of Christ. Those sacrifices were prophetic symbol which foreshadowed the once and for all time substitutionary sacrifice of Christ. Those animal sacrifices were merely types and shadows. Jesus the true Lamb of God, who was slain for our sins is the antitype of those types and shadows. Jesus Christ is the substance of those sacrifices. He was innocent just like the lamb, he was without spot or wrinkle, which depicts his sinless nature. As the lamb died in the place of the offender, so Christ died as our substitute, obtaining eternal redemption for us. Jesus Christ is the Lamb of God that took away our sins by the sacrifice of himself (John 1; 29).

Why was the sacrificial system brought to an end?

Many people have been wondering why the sacrificial system was made obsolete. I answer by saying that it was made obsolete, because Jesus has died, he has fulfilled the ceremonial law in it's entirety. All those sacrifices were pointers, they pointed to the coming and the vicarious sacrifice of Christ. Since, Jesus has died for our sins, there is no need for those sacrifices any longer, they have served their purpose. Our sins are forgiven once and for all time by the death of Christ in our stead (Hebrews 8; 12).  At the death of Christ on the cross, the thick veil which separated the holy place from the most holy place was rend asunder from top to bottom, which signifies that the way into the innermost place is now accessible for all those who trust in him for salvation (Matthew 27; 50-51, Hebrews 5; 9).

Why can't the blood of animals save, but the blood of Jesus alone?

The author of Hebrews made it clear to us in his epistle: For it is impossible for the blood of bulls and goats to take away sins (Hebrews 10; 4). The main reason why the blood of those animals could not save them was because, it is not possible for the blood of bulls and goats to take away sin. Those sacrifices provided temporal remission for their sins, that is why they had to offer the same sacrifices year after year. But the sacrifice of Christ is potent and efficacious enough to completely expiate the sins of our entire lives. Because our sins are forgiven, God said: "For I will be merciful to their iniquities, And I will remember their sins no more" (Hebrews 8; 12). The blessedness of salvation can only be found in the person and finished work of Christ. Peradventure, if you have no personal relationship with Christ, the blood of Jesus Christ has the power to wipe away your sins once and for all, only if your faith rests in him alone for salvation (Revelation 1; 5).  God bless you

A thought to ponder

Jesus Christ is the Lamb of God that took away our sins by the sacrifice of himself

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