CAIN AND ABEL

Coming fast on the heels of the creation account, the serpent's temptation, and Adam and Eve's forced exit from the Garden of Eden, Genesis 4 introduces some notable firsts:

• The first birth: Cain.
• The first sacrifices: Cain brings "fruit of the soil" and Abel brings some of the firstborn from his flock.
• The first use of the word "sin": God warns Cain about sin "crouching at the door" and "wanting" him.
• The first murder: Cain kills Abel.
• The first mention of blood: Abel's blood cries out to God.
• The first city: Cain builds it after he is punished by God for Abel's murder.
• And the chapter ends with "men beginning to call on the name of the LORD".

Another notable aspect of the story is what is NOT there.

• No clear explanation of why God prefers Abel's sacrifice.
• No overt expression of wrath by God over this first instance of one human killing another. 
• No sense that Adam and Eve had passed on some genetic, corrupted sinful nature to their offspring. Abel made good choices and Cain made bad choices.

New Testament authors fill in a couple of the gaps:

• Hebrews 11:4 By faith Abel offered God a better sacrifice than Cain did. By faith he was commended as righteous when God gave approval to his gifts. 
• 1 John 3:12 Do not be like Cain, who belonged to the evil one and murdered his brother. And why did Cain slay him? Because his own deeds were evil, while those of his brother were righteous.

Interestingly, Jesus implies that Abel was a prophet in some sense, although that word does not appear in Genesis 4. In rebuking the Pharisees, Jesus said,

Luke 11:47 Woe to you! You build tombs for the prophets, but it was your fathers who killed them. 48 So you are witnesses consenting to the deeds of your fathers: They killed the prophets, and you build their tombs. 49 Because of this, the wisdom of God said, ‘I will send them prophets and apostles; some of them they will kill and others they will persecute.’

50 As a result, this generation will be charged with the blood of all the prophets that has been shed since the foundation of the world, 51 from the blood of Abel to the blood of Zechariah, who was killed between the altar and the sanctuary. Yes, I tell you, all of it will be charged to this generation.

In the broadest sense, a prophet was one who highlighted God's standards and warned those going astray. 

It is not recorded that Abel said a single prophetic word to his brother. It seems Abel's life and example were enough to inspire his brother's hatred.