When Adam and Eve ate the fruit in the garden they destroyed the peace they enjoyed with God. Peace between them was eroded when Adam so quickly blamed Eve and Eve simply blamed the serpent (genuine peace does not exist when we are too proud to admit our own sins). But it was their son who destroyed peace with others most decisively.
Both Cain and Abel brought an offering to the Lord (see Genesis 4, the Tawrat). God accepted Abel’s offering, but not Cain’s. This made Cain angry so that God graciously cautioned him, “Why are you angry, and why has your face fallen? If you do well, will you not be accepted? And if you do not do well, sin is crouching at the door. Its desire is for you, but you must rule over it” (Genesis 4:6-7).
God personified sin as a predator who desired to destroy Cain and rule over him. If Cain is to do well, he must overcome his sin and rule over it. He must not let himself be a slave to his own sin. Of course, he failed. Sin won and Cain killed his brother. This is the first murder in human history. Any pretension of peace in the family was destroyed. A man killed his own brother. It does not take long for sin to destroy peace with God and peace with others.
The story of Cain and Abel (Qabil and Habil) is also found in the Qur’an (Surah 5:27-32). The way the Qur’an sums up the story is very profound. In verse 32 it says, “For this reason did We prescribe to the children of Israel that whoever slays a soul, unless it be for manslaughter or for mischief in the land, it is as though he slew all men.” Killing one is like killing all. Men and women were meant to live in peace. Murder destroys this peace, not just for the one killed, but in a very real sense for us all.
Jesus Christ raised the stakes considerably. He taught us that merely not murdering someone is not enough. There is a greater problem in our hearts. He said in the Injil, “You have heard that it was said to those of old, ‘You shall not murder, and whoever murders will be liable to judgment.’ But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire” (Matthew 5:21-22).
Later in the Injil Jesus the Messiah is contrasted with Cain (1 John 3:11-18). We are called to love one another—to not be like Cain, for he killed his brother. Instead we are to be like the Lord Jesus, “By this we know love, that he laid down his life for us, and we ought to lay down our lives for the brothers” (1 John 3:16). Not murdering is not what it means to love. Not murdering is not the restoration of peace. Laying down our lives is what it means to love. Laying down our lives (both literally and metaphorically) is what it takes to restore peace.