Genesis 4:6 And the Lord said unto Cain, Why art thou wroth? and why is thy countenance fallen? 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.
[Patriarchs & Prophets pp 73>74] When Cain saw that his offering was rejected, he was angry with the Lord and with Abel; he was angry that God did not accept man's substitute in place of the sacrifice divinely ordained, and angry with his brother for choosing to obey God instead of joining in rebellion against Him. Notwithstanding Cain's disregard of the divine command, God did not leave him to himself; but He condescended to reason with the man who had shown himself so unreasonable. And the Lord said unto Cain, “Why art thou wroth? and why is thy countenance fallen?”
Through an angel messenger the divine warning was conveyed: “If thou doest well, shalt thou not be accepted? And if thou doest not well, sin lieth at the door.” The choice lay with Cain himself. If he would trust to the merits of the promised Savior, and would obey God's requirements, he would enjoy His favor. But should he persist in unbelief and transgression, he would have no ground for complaint because he was rejected by the Lord. But instead of acknowledging his sin, Cain continued to complain of the injustice of God and to cherish jealousy and hatred of Abel.
He angrily reproached his brother, and attempted to draw him into controversy concerning God's dealings with them. In meekness, yet fearlessly and firmly, Abel defended the justice and goodness of God. He pointed out Cain's error, and tried to convince him that the wrong was in himself. He pointed to the compassion of God in sparing the life of their parents when He might have punished them with instant death, and urged that God loved them, or He would not have given His Son, innocent and holy, to suffer the penalty which they had incurred.
Romans 5:7 For scarcely for a righteous man will one die: yet peradventure for a good man some would even dare to die. 8 But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us.
May God add His blessing to the study of His word. “Good night” and God bless!