There is a connection between chapter three and chapter four. In chapter three we see the beginning of sin in man, in chapter four we read of the progression of sin. In chapter three the sin was against God and chapter four we see the sin against man who was made in the image of God

The name Cain means a smith or a spear.

The name Abel means a breath or vapor. It suggests a brief life.

Adam and Eve had many sons. Cain and Abel seem to be the two oldest. The Jewish historian, Josephus says that there were probably 33 sons and 23 daughters.

V 4. And Abel brought of the first born of his flock and of the fat portions. And the Lord had respect and regard for Abel and for his offering. Hebrews 11:4

How different these two men were. Both were sons of fallen parents. Both were raised in the same place and in a similar manner. Environment is not the deciding factor. Everyone has freedom of choice.

Substitution, a life for a life, was established in the garden of Eden. Adam as priest of the family had direct knowledge of this, he would have passed this information on to his children. Abel's offering is a sign that he did.

Abel brought, indicates that God had established a definite place and time for worship. Neither Cain nor Abel would have known of the sacrifice that had been appointed by God unless they had been told by Adam. Faith comes by hearing. Romans 10:17. By faith Abel brought and offered. Hebrews 11:4

The fat portions reveal that the animal was slain and the fat portions burned. It is likely that even then the offerings were accepted by fire. Lev. 9:24. Consider Elijah on Mount Carmel and the fire from God mentioned in Isaiah 50:10-11

Cain insisted on bringing an offering produced by his own effort. One that he had struggled to produce from a cursed earth. He had pride in the products he had grown. In bringing a bloodless offering, he denied that he was a sinner, with need of forgiveness. I’ve often wondered if the saying "can’t get blood out of a turnip" originated with this event.

Cain's offering was no more than a token of acknowledgment. He came without faith in the plan of God. Many honor God with their lips while their hearts are far from Him. They pose as worshipers while living to please themselves. Cain was the first hypocrite. He would not obey the will of God, yet covered his rebellion by pretending to be a worshiper. A hypocrite is defined as one who says he has moral standards to which his life does not conform. This person is play acting, exhibits falseness, phoniness and is sometimes called a double dealing faker or a Pharisee

God rejected Cain's offering. The penalty for sin is death, life is in the blood. Leviticus 17:11-14 A sin offering requires the shedding of innocent blood. Thank God for Jesus, the lamb who takes away the sin of the world. When we ask Him to forgive us for our past and come into our life in the future. We are made clean, in God's eyes, with the pure sacrifice of Jesus.

Cain had what we would call a green thumb. He had talent. People often think that God should be thrilled with their talents. What God is looking for is a humble and contrite heart, Psalms 51:17. When we come before God in the manner He desires, then He blesses the talents that are built into us.

Contrite only means remorseful or penitent in present day uses, in times past packages of Talc bore the words, crushed stone. The Hebrew word for contrite is Dacka’. If we have a hard heart we need to let the hammer of God’s word (Jeremiah 23:29 amp.) Break through the crust of hardness and soften our hearts. If we consider what we mean when we say, " there goes a hard hearted person," very likely we will not want to be one.

Anger is defined as a belief, that we or someone we love, has been unfairly treated. Remember, he that is slow to anger is better than the mighty, he who rules his own spirit is stronger than one who takes a city. Proverbs 16:32

Our faces betray the emotions we are feeling. When we stomp around looking like a thunder cloud that is about to rain on somebodies parade, it is very obvious to everyone. What we feel in our souls is shown on our faces. God also notices the attitudes that we have and the looks on our faces. He gives us an opportunity to bring a proper sacrifice. He is not willing that any should perish. A proper sacrifice is not the works of our own hands. Hebrews 9:22 and Isaiah 50: 10-11.

I looked this verse up in four different versions of the Bible. Amplified (as printed above) sounds like an order. Living Bible indicates that we have the ability, King James version denotes a promise and the New Kings James reads like a suggestion that denotes ability. As in all things, the Lord does not ask us to do something by ourselves. He gives us the power to do what He asks. Micah 3:8, Zechariah 4:6, Acts 1:8 and Ephesians 3:16-20

Remember, where sin is concerned, there is a difference between, "I stumbled and fell in" and "I did it, I liked it, and I plan to do it again." The Word indicates that we can be angry and sin not in Ephesians 4:26-27. If we let the sun go down on our wrath we may find ourselves holding grudges. The nature of the devil is to bear grudges a good reason for us not to do so. The angry person evaluates other peoples behavior as being directed toward themselves, which may or may not be true. Cain probably thought that Abel was trying to make him look bad.

Well doing consists of more than the act itself. The inner motive must be right. The Lord said, Come let us reason together. Cain was not receptive to reason, because he was angry. Anger blows out the reason of our minds. Cain did not listen to God. He began plotting to get even with Abel. If we do not master sin, it will consume us, one bite at a time. We do not usually just leap into sin, most often we move gradually toward the abyss, lose our footing and plunge in. Recall the steps that Eve went through. She looked (a glance) she saw (considered) and then she took. In and of ourselves we cannot master sin in our lives. It is through the power of the risen Lord living in us that we become over comers. Read Romans chapter seven.. 

The evidence here points to premeditated murder. Satan is after the seed of woman, because he did not know which seed would bruise his head. By entering into Cain, he could destroy both of them. Death eliminated Abel. Sin eliminated Cain. Neither of them could produce the seed that would conquer Satan. The devil must have felt like celebrating, it wasn’t the last time he was wrong. Matthew 2:16-18 and 28:6 

Notice that even though they were out in a field where there was no one to observe Cain’s crime, it did not go unnoticed We may be sure that our sin will find us out. Numbers 32:23, Luke 12:3.

Hebrews 4:13 amplified "And not a creature exists that is concealed from His sight, but all things are open and exposed, naked and defenseless to the eyes of Him with Him Whom we have to do."

Have you ever had someone hate you, just because you were doing the right thing? That’s what happened here, read I John 3:12. Cain had no reason to be angry at God. It was his own rebellious actions that caused the rejection of his offering. Neither did he have a reason to be angry at Abel. He was angry at God and wanted to strike at Him, not being able to reach God, he struck at one that God loved. We are guilty of murder fairly often. "Not me!" you say, "I've never murdered anyone." Unless we are very unusual people, we are just as guilty as Cain. Anger breaks lose and we commit murder before we realize it. Not physical murder, but murder just the same. We can assassinate someone's reputation in a flash with our words.

A famous 19th century attorney (Clarence Darrow) once said, "I have not killed anyone, but I frequently feel joy when I read the obituaries." We sometimes have murderous thoughts. Jesus taught, if we continue to think and speak ill of someone, we will not escape punishment. He who hates is a murderer at heart. 
1 John 3:15. We must be quick to repent, quick to believe and quick to receive His blessing in our lives.

Matthew 5:21-22 Ye have heard that it was said by them of old time, Thou shalt not kill; and whosoever shall kill shall be in danger of the judgment: But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.

Judgment in this case, referred to an eye for an eye. Genesis 9:5-6. Being in danger of the council means you can be sued.

Cain became the first murderer and Abel became the first martyr. Abel died for his religious beliefs. 

God's first question to man was, "Where are you?" His second question to man was, "Where is your brother?" He is still doing that. After we discover where we are, and get our lives in order, we are to be concerned for our brothers.

The Lord gave opportunity to Cain, for confession and forgiveness. The opportunity was rejected, answered with a lie and insolence. God only pardons those who confess.

From this point on there are two ways that run through the history of mankind. The way of Cain and the way of Abel. The way of unbelief, or the way of the believer. We fool ourselves if we think that we can sit on the fence between belief and unbelief. There are only two kingdoms. The kingdom of light, where Jesus is king of kings. Or the kingdom of darkness, ruled by Satan. We are in one or the other. There is no in between. The devil tries to fool us into thinking there is man’s way, the word says there is a way which seems right unto man but the ends there of are death. Proverbs 14:12. Jesus says, "I am the way the truth and the life." John 14:6

The way of Cain: Cain represents the natural man. Cain established the first false religion. A religion of the flesh and self-satisfied justification by works. There are millions who still follow his way. Doing many good deeds in an attempt to earn their way into heaven. They think they can hold their good works before God and find acceptance. It won't work. God will not accept an offering unless it is one appointed by Himself. Jesus is that offering. Those who follow the way of Cain will end in the lake of fire. People who are self righteous and rely on their own good works (fig leaves) are fooling them selves. Remember in all of the Bible there is only one thing that Jesus cursed while He was on the earth. It was the fig tree that pretended to have fruit by a show of lots of leaves. Mark 11:23.

The way of Abel: Abel represents the spiritual man who accepts the sacrifice that Jesus made and rests in His finished work.. The humble acknowledgment that sin demands death and the reliance of the guilty on the sacrifice appointed by God Himself. Those who follow the way of Abel will end in the heavenly Jerusalem. Romans 6:16 Death is the wages of sin, either we must die or someone must die in our place. Mercy can only come after justice is satisfied. God gave the basic truth of substitution in the third chapter of Genesis. The just for the unjust, the perfect one for the fallen ones. REMEMBER we become the servant of the one we habitually follow.

We can be sure that our sin will find us out. No matter where we try to hide it. It will surface. Abel's blood like the blood of the martyrs in all ages, cries out for vengeance.

Revelation 6:9 And when he had opened the fifth seal, I saw under the altar the souls of them that were slain for the word of God, and for the testimony which they held: And they cried with a loud voice, saying, How long, O Lord, holy and true, dost thou not judge and avenge our blood on them that dwell on the earth?

Hebrews 12:24 And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaks better things than <that of> Abel.

While the blood of Abel cries out for vengeance, the blood of Jesus cries forgiveness.

Cain who loved to till the earth and plant seeds had this pleasure taken away. Now the earth would not yield its bounty to him. He would not be allowed to settle on the land. The farmer must become a city dweller. His green thumb died and turned brown. Cain’s bad attitude toward his brother Abel was devastating, he could have gone on to be the biggest producer of farm products and sold all of his goods to Abel and his descendants. Think about all the lands where people are starving because of blood spilled on the ground.

Cain who has had little to say, now finds his voice. His only words prior to this time have been short and terse. I do not know (lie) and am I my brothers keeper? Now, faced with the results of his actions, standing before the judgment seat, he decides to be his own advocate. In the secular world it is said, "He who has himself as a lawyer, has a fool for a client" this is also true in the spiritual. We have an advocate. 1 John 2:1. He should have thrown himself on the mercy of the court and allowed the court to appoint an advocate for him. There is no concern for what he has done, only concern for himself. He is not sorry that he killed his brother. Not sorry that he caused his parents much pain, just sorry that he was caught. 2 Corinthians 7:10. He denies responsibility for wrong doing. Tries to shift blame from himself, on to God. He says, "You have driven me out." away from your presence and away from my farm.

The presence of God which meant little to him, now seems precious. He realizes that without God's protection he is subject to violence. He is afraid. When we are involved in sin, paranoia will follow. Fear is not sent by God. God is opposed to fear.

2 Timothy 1:7 For God hath not given us the spirit of fear; but of power, and of love, and of a sound mind.

God's reaction to fear, is to calm it. Notice that the messengers from God have always started with, "fear not."

Vengeance shall be taken. Vengeance is mine says the Lord.

Set a mark on Cain. No description of the mark is given. Some think that it was something on his forehead. Others think it was something awesome about his appearance, that caused others to avoid him. The setting of the mark, was an act of mercy. God guaranteed that Cain would have an extended opportunity to repent.

There is no record that Cain ever came into the presence of God again. Notice that it was Cain who went away from God, not God from Cain. Cain chose his land and built a city. When we choose for ourselves, we may have opportunity to wish we had not. Better to ask of God, where He would like for us to be.

There was at least 129 years between the birth of Cain and the birth of Seth. It is probable that Adam and Eve had many sons and daughters during this time.

Such marriages could not be avoided in the beginning of man's history. Remember that the children of Adam were not merely a family, but the whole human race. Soon the need for marriages of this sort disappeared. During the time of Moses marriages between near kin were vigorously prohibited.

It was sometimes the custom of men, but never the will of God, for men to have more than one wife at a time. Any way, most men find that one wife is trouble enough.

This was a very materialistic society.

Musical talents.

I wonder if Lamech was not also an abuser of his wives and children, verse 23 sounds like a threat. Lamech was a polygamist and a murderer who gloated over his crimes. He seems to think he is the greatest of them all and not even God could bring him down.

Cain, with indifferent heart, went "his own way," without humility or faith. His family developed along material lines. They built cities and began arts and industries. They bred polygamy and violence. The list of Cain's descendants ends with the remarks of a man who was given over to violence. Cain's sin multiplied several times over.

Now in verse 26 we see the righteous seed restored. This may have been the beginning of public worship.

Always remember that Satan cannot create anything. He is an imitator of God, he copies but with a reverse twist. So, there is an Egyptian god of evil and chaos who is called Seth.

The main purpose of this record is to show the link between Adam and Noah. Not all of these men were godly. Enos was not but still through the line of Seth we arrive at the righteous Noah. People lived a long time because God built longevity into man. As a result of abusing our bodies and speaking death with our mouths, we have shortened our life spans. We talk death instead of life. I am starving to death, I am tickled to death, I am freezing to death, I am so hungry I could die. My feet are killing me. When we speak death we shorten our life. Sing old rocking chairs got me...and pretty soon it does.

The result of sin is death, and some of us die sooner than others. Not necessarily because of personal acts of sin, but because of the sentence of death that came into the world after the fall. It took Satan many years to get it down to the point where man would die early. We have helped him by speaking his language of death, devastation and destruction. We have been committing suicide with our mouths. When we speak life, we add life to our life. Jeremiah 18:18,Psalms. 50:23, Proverbs 12:13-14, Proverbs 18:20-21, Matthew 12:35, Proverbs 16:23-24 and many others prove that we can either speak the language of God or the language of Satan.