Allah describes the evil end and consequence of transgression, envy and injustice in the story of the two sons of Adam, Habil and Qabil. One of them fought against the other and killed him out of envy and transgression, because of the bounty that Allah gave his brother and because the sacrifice that he sincerely offered to Allah was accepted. The murdered brother earned forgiveness for his sins and was admitted into Paradise, while the murderer failed and earned a losing deal in both the lives. Allah said,
(And recite to them the story of the two sons of Adam in truth;) meaning, tell these envious, unjust people, the brothers of swine and apes from the Jews and their likes among mankind, the story of the two sons of Adam, Habil and Qabil, as many scholars among the Salaf and later generations said. Allah's statement,
In these verses, Allah Ta` a1a has instructed the Holy Prophet ﷺ that he should relate the story of the two sons of Adam truthfully to the people of the Book, or to the whole Ummah.
People who are blessed with insight into the Holy Qur'an know that it is no book of folklore, fiction or history where the purpose is to relate an event from the beginning to the end. But, events of the past and accounts of earlier peoples carry many lessons and wise counsels within their fold. That is the real essence of history. Then, in them, there are such conditions and circumstances as form the basis of different religious injunctions. In view of these very beneficial considerations, the Qur'an employs a methodology of its own throughout the text. It would, when the occasion warrants, narrate an event. Most of-ten, it would not narrate the whole event in one sequence and at one place. In fact, preference is given to narrating a particular segment from it which bears some element of purpose and is relevant at the given place.
Whatever a man receives in this world is bestowed by God. Therefore, being jealous of a person on seeing him well situated in life and then inflicting harm on him amounts to trying to nullify God’s plan. Such a person is to some extent given the scope to do whatever he likes in this world of trial, but in the eyes of God, he is the worst sinner. Abel drew the attention of his elder brother, Cain, to this fact. This created some hesitation in his mind. He realised that he was bent on killing his younger brother without any justification. But the feeling of jealousy in him did not cool down. He invented excuses to justify his action. Ultimately, his inner struggle resolved itself and rest in his self-devised justification and he proceeded to kill his brother. The voice of conscience is the voice of God. A question arising in a man’s conscience about any action of his amounts in fact to his facing a test. A man is successful if he gives a positive response to the voice of his conscience, but if in taking the shelter of false excuses he suppresses the voice of his conscience, then he has failed.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.
