Have you ever wondered why God respected Abel's offering, but did not respect Cain's offering (Genesis 4:4-5)? Often times we are taught that Abel had a good attitude when he gave and Cain did not or that Cain didn't give his best. However, this is reading into the text of God's word. There's nothing there that really says that. It may well have been, but that's not information that the Holy Spirit saw fit to provide. All we know is that Cain brought an offering from the fruit of the ground, as he was a farmer, and Abel brought of the firstborn of his flock and of their fat (Genesis 4:3-4). The most we can say is that Abel gave of his first and best. However, I believe there's more to it than that.
Principle: The forgiveness of sin requires bloodhshed. "And according to the law almost all things are purified with blood, and without shedding of blood there is no remission" (Hebrews 9.22). Remission just means fogiveness, aquital, release, or pardon. For God to remain a "just God" He has to execute judgement on sin. He can't just let it go. Blood must be shed. Innate in all of us is the idea that someone has to "pay" when there is an injustice. When Adam and Eve, Cain and Abel's parents, sinned God killed an animal (Genesis 3:21) to cover their nakedness - their sin. God allowed a temporary substitution, but blood still had to be shed. All of the Old Testament sacrifices and offerings prescribed for the temporary removal of sin required an animal to die in man's place. Thank offerings could be grain and wine, but anything related to removing sin required blood. Why?
Because Jesus was the lamb slain from the foundation of the world (Revelation 13:8). Every time there was a death of an animal for man's sin, whether they knew it or not, they were looking forward to Jesus laying down his life for us all! Hebrews 9:12 says, "Not with the blood of goats and calves, but with His own blood He entered the Most Holy Place once for all, having obtained eternal redemption. " Hebrews 10:1 tells us that those sacrifices were just shadows or images pointing to the once and for all perfect sacrifice of Jesus that would forever purge us of the condemnation, judgement, for sins. Those animal sacrifices were an ongoing reminder of sin. They never removed sin because they kept having to be offered over and over again (Hebrews 10:1-4).
Now back to Cain and Abel. Abel's sacrifice pointed to Jesus, Cain's sacrifice did not. Abel was looking by faith to that promised Seed who would bruise the serpents head at Calvary (Genesis 3:15). How do we know? Isn't that an aweful lot to suppose to be in Abel's head? Well, let's look at Hebrews 11:4 - "By faith Abel offered to God a more excellent sacrifice than Cain, through which he obtained witness that he was righteous, God testifying of his gifts; and through it he being dead still speaks". How was it that he was righteous? Was he righteous because of his good works, his deeds? No. The word says, there is none righteous, no not one (Romans 3:10) and all our righteousness is as filth rags - literally a dirty sanitary napkin (Isaiah 64:6). By the deeds or works of the law, no flesh is justified (Romans 3:20). Abel was made righteous not by his works, but by his faith in the coming messiah! Amen! Still don't believe me? Look a litter further to Hebrews 11:7. It was by faith that Noah became the heir of the righteousness which is according to faith. An heir doesn't work for something. He just receives it because it was legally bestowed on him. The scriptures says a similar thing of Abraham who believed God (by faith) and it was accounted to him for righteousness (Genesis 15:6, Romans 4:22, Galatians 3:6). Abel did not look to his own works or effort for righteousness, but to the perfect sacrifice of Jesus. He believed in the promised Seed and obeyed God's prescribed method for the removal of sin rather than his own way, his own effort.
Now, let's contrast Cain. Can was a "tiller of the ground", a farmer (Genesis 4:2). Now let's see what the last thing was that God said about the ground.
Then to Adam He said, "Because you have heeded the voice of your wife, and have eaten from the tree of which I commanded you, saying, 'You shall not eat of it': "Cursed is the ground for your sake; In toil you shall eat of it All the days of your life. Both thorns and thistles it shall bring forth for you, And you shall eat the herb of the field. In the sweat of your face you shall eat bread Till you return to the ground, For out of it you were taken; For dust you are, And to dust you shall return." (Genesis 3:17-19).
Cain's offering, the fruit of the ground, didn't point to Jesus. It pointed to hard work, self effort, and little produce. Whether he knew it or not, his offering was reminiscent to God of righteousness by works by which we already know that no one is justified (Galatians 2:16). The works of the law (self-effort, self-righteousness) produce the works of the flesh (Galatians 5:18-21). The outward manifestation of being under law produces all the sins listed. In Cain's case, he manifested hatred and then murder when he killed his brother (Genesis 4:8). Self-effort under law, instead of looking to the cross of Jesus, breeds frustration for not measuring up and eventually manifests something bad as it did with Cain.
Friends, God doesn't want us to work for righteousness, he wants us to receive it by faith and then naturally produce the good fruit we desire (Galatians 5:22-23). He doesn't want us to toil by the sweat of our brow for what He would freely give. Our Lord says, "Come to Me, all you who labor and are heavy laden, and I will give you rest" (Matthews 11:28). Let's rest in Him. Rest in the finished work of Jesus who has perfected us forever!