When God questioned Cain as to the whereabouts of his brother Abel, whom he had murdered, Cain responded first with a lie saying that “I know not” and then counter-questioned God “Am I my brother’s keeper?” God had given Cain a chance to be accepted even though his offering was not (Genesis 4:6-7). At this time, Abel was still alive, but instead of heeding to God’s voice, Cain rejects God’s offer to be accepted. Instead he let’s sin rule over him. He talks to his brother Abel and when they are in the field, Cain rises against his brother Abel and slays him (Genesis 4:7-8). Cain murders his brother and then lied about his murder to God, the omniscient.

Cain willfully chose to blaspheme by rejecting the conviction of the Holy Spirit of God and letting sin rule over him. Cain murdered and lied, because his life was driven by and under the influence (DUI) of the devil. Jesus referred to the devil as a murderer and liar from the very beginning (John 8:44).  Notice the sins of Cain was murder and lies. Notice the devil is the father of lies and a murderer.

Points to ponder:
When we willfully sin against God, rejecting the conviction of the Holy Spirit of God, we blaspheme against God and are under the influence of the evil one i.e., our lives are driven by the devil. Let us not willfully reject the conviction of the Holy Spirit of God (John 16:8-9) and blaspheme against him, lest we shall be like Cain DUI.

Genesis 4:7-9 (KJV)
7 If thou doest well, shalt thou not be accepted? and if thou doest not well, sin lieth at the door. And unto thee shall be his desire, and thou shalt rule over him.
8 And Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him.
9 And the Lord said unto Cain, Where is Abel thy brother? And he said, I know not: Am I my brother’s keeper?

John 8:44 (KJV)
44 Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.