Adam was in a dilemma. He wanted peace and harmony in his family, so he invoked Allah for help. Allah commanded that each son offer a sacrifice, and he whose offering was accepted would have right on his side. Abel offered his best camel, while Cain offered his worst grain. His sacrifice was not accepted by Allah because of his disobedience to his father and the insincerity in his offering.
This enraged Cain even further. Realizing that his hopes of marrying his own beautiful sister were fading, he threatened his brother: "I will kill you! I refuse to see you happy while I remain unhappy!"
Abel, feeling sorry for his brother, replied: "It would be more proper for you, my brother, to search for the cause of your unhappiness and then walk in the way of peace. Allah accepts deeds only from those who serve and fear Him, not from those who reject His commands."
Related Quran Ayaaths of this Hadith.
Surah 2 : Ayah 31 Surah 2 : Ayah 33 Surah 2 : Ayah 34 Surah 2 : Ayah 35 Surah 2 : Ayah 37 Surah 7 : Ayah 11 Surah 7 : Ayah 19 Surah 7 : Ayah 26 Surah 7 : Ayah 27 Surah 7 : Ayah 31 Surah 7 : Ayah 35 Surah 3 : Ayah 33 Surah 3 : Ayah 59 Surah 5 : Ayah 27"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari