"Yes... um, yes. Here I am."
"Where is your brother?"
"Abel. Where is Abel your brother ?"
"Um, I, well you see... I'm, uh I'm not sure. I don't know."
"Cain, where is your brother?"
"I don't know! Am I my brother's keeper?"
"Cain. What have you done?
"Well, I, um, I―"
"Silence! Listen. I can hear your brother's blood crying out to me from the ground. The soil that you have tended and tilled has been filled with your brother's blood. You are cursed. You will no longer work that field or any other, for the earth will no longer produce crops for you―"
"What? But I, how―"
"―and you will be forced to wander the earth."
"But, what... but... My punishment is more than I can bear!"
Judgement! The blood of Abel cried out for judgement. Though Cain may have believed that he could conceal the murder of his brother, he was soon confronted by God about his actions. He lied. He evaded. But the Lord of heaven and earth told him that, although his brother was not alive to bear witness to what had occurred, Abel's blood was crying out and giving testimony to Cain's actions. And so Cain was put under a curse. He was sent out of God's presence, his livelihood was taken from him, and he was forced to wander the earth.
In the letter to the Hebrews, the author writes that Jesus' blood speaks a better word than the blood of Abel. Its testimony is much greater. Instead of a curse, the blood of Jesus brings a blessing. Instead of crying for judgement, His blood speaks peace. Instead of innocent blood bringing enmity with God and separation from God, it is only by His blood that we can stand acceptable in God's presence. Jesus' blood speaks of better things.