At the most basic level the answer to this question is “Because God has ordained it so”. However He has graciously made part of the answer known in His word. We learn from Genesis 3 for instance that death is the penalty for sin. “For in the day thou eatest thereof thou shalt surely die”. So it understandable that if the death can be dealt with, so can the sin. If the penalty for the sin can be borne, then the cause of the penalty can be forgiven.
One of the standard texts in the Scriptures on this subject is Leviticus 17:11, which reads:
“For the life of the flesh is in the blood: and I have given it to you upon the altar to make an atonement for your souls; for it is the blood that maketh an atonement for the soul”.
Chapter 17 of Leviticus gives us God’s mind about blood-shedding by sacrifice. In verses 1-7 we learn that He forbade the children of Israel from killing an animal for sacrifice and then omitting to bring it to the tabernacle so that the blood could be sprinkled on the altar. This was so that they were not tempted to offer sacrifices to devils as the Canaanites did, see verses 6 and 7. It was also because God reserved the blood for Himself, for it had special meaning to Him. This was why in verse 10 the Israelites are forbidden to eat blood in any form. Blood congeals after it has left the body, and so may be eaten. By eating blood a man has taken to himself that which is exclusively God’s. This prohibition is carried over into the New Testament, and still applies today, for Acts 15:23-29 gives the contents of a letter sent from the apostles to Gentile assemblies, and in it they, and we, are required to “abstain from meats offered to idols, and from blood, and from things strangled, and from fornication: from which if ye keep yourselves, ye shall do well”.
Returning to Leviticus 17. We learn in verse 11 the reason for this prohibition, the verse beginning with the word “for” or “because”. “The life of the flesh is in the blood” is the reason. Note it is the life of the flesh, not just of the body. The flesh is a wider thought, and takes in the whole life of the animal whose blood is shed. The word for flesh used here is often translated “soul”. We learn that the blood represents the total life of the creature.
Verse 11 goes on, “And I have given it”. The word “I” is emphatic; “I the God of Israel”, or, “I the God who created all things for Mine own pleasure”. It is He alone that has ordained this principle, so it is not cultural, or traditional, but of His appointment. By this we learn that the principle behind blood shedding is of God, and is not the blood-thirsty idea of heathen savages. Man may despise it if he will, and call it “the doctrine of the shambles”, (the shambles being the meat-market in ancient cities), but then “the wisdom of the world is foolishness with God”, 1 Corinthians 3:19.
The blood then is “given” in a particular way. It is not the blood flowing through the veins of a living creature, but the blood that has flowed out of its veins in death. In other words, the blood is the sign of death, not life. So it is that even if a man is murdered in a way that did not involve the shedding of blood, yet it is still called “the shedding of blood”. God’s command is that “Whoso sheddeth man’s blood, (i.e. murders), by man shall his blood be shed”, (i.e. be executed), Genesis 9:6. Just as a murder may not involve the shedding of blood, so the execution need not either. The idea in both cases is the taking of life, and that life is represented by the blood.
Our verse goes on to say, “to make an atonement for your souls”. So the shedding of blood is the inner core of the concept of atonement.
The question that confronts us, however, is how this should be. We might respond by repeating that since God has ordained that it should be so, we should not enquire further. But it is surely in order to meditate upon this important matter. We could think like this. God is the Living God, so to Him death is alien and strange, and cannot stand in His presence, for it is contrary to His being. Death is also alien to Him because it is a powerful evidence of separation. When we physically die, our body, soul and spirit part company, for “the body without the spirit is dead”, James 2:26.
Life, on the other hand, speaks of fellowship. We are given natural life so that we may share the good things that our Creator gives to us richly to enjoy, 1 Timothy 6:17, and those who have been given eternal life are able to enjoy the things of God, as we learn from 1 John 1:1-4.
Sin is also alien and strange to God, and something with which He cannot have fellowship. So we may easily see that where there is sin, there must also be the separation of death too, for God must mark His disapproval of sin by distancing Himself from it by banishing the sinner. Adam found this out when he sinned, for he was cut off from fellowship with God. He was allowed to continue living naturally so that he could repent and turn to God for forgiveness, but as far as fellowship with God was concerned he was “alienated from the life of God”, Ephesians 4:18.
The apostle Paul summed up these things in Romans 5:12 when he wrote, “Wherefore, as by one man sin entered into the world, and death by sin: and so death passed upon all men, for that all have sinned.” So sin has been introduced into the world of men through Adam’s fall, and as a result death has passed on to us as a sentence from God. We prove that we have the sin-principle within us by all sinning.
But there is another side to this, as the apostle goes on to declare. “For as by one man’s disobedience many were made sinners, so by the obedience of one shall many be made righteous”, verse 19. We are being introduced here to God’s answer to Adam’s act of disobedience. It is nothing less that the complete obedience of Christ to His Father’s command to die at Calvary. This act of going to Calvary and dying there is called an act of righteousness in verse 18, for that is the meaning of the word translated “righteousness” there. The death of Christ was a judicial act, designed to remedy the unrighteous act of Adam in sinning. It was also the act of one who is perfectly and totally righteous, and which therefore gives supreme satisfaction to God.
It is extremely important to see that the Lord Jesus is perfectly sinless in every aspect. This is vital, for if there is any suspicion of sin about Christ, His death at Calvary was not a righteous act, and sin is not dealt with. Now if one who is perfectly sinless, and who therefore has not forfeited His right to live, goes willingly into death in order to deal with sin, then by so doing, He shows Himself superior to death. Death only has authority over those who have sinned, but if death can be experienced by one who has not sinned, and that same one can emerge in resurrection, then death has been rendered powerless in principle. Just as David slew Goliath with Goliath’s own sword, (the weapon he would have used to slay David), so Christ has used death to slay death. By so doing, He also “destroyed him that had the power of death, that is the devil”, Hebrews 2:14.
He has “abolished death, and brought life and immortality to light through the gospel”, 2 Timothy 1:10. The believer is “dead with Christ”, Colossians 2:20, for God, foreknowing who would believe, reckoned believers to have died when Christ died. They share in His triumph over death.
So it is that God’s answer to sin and death is His sinless Son, who surrendered Himself to the will of His Father, and “became obedient unto death, even the death of the cross”, Philippians 2:8. And this is what Isaiah meant when he said that Christ “poured out His soul unto death”, for as we have seen, the life of the soul is in the blood, and when he surrendered to death that was the same as the shedding of His blood. The physical fact that the blood of Christ did come from His wounds is not the point. The real point is that He gave up His life. As we have seen from Leviticus 17:11 this need not involve the shedding of blood at all in the physical sense.