Abel and Cain

According to the Holy Bible and the Holy Qur'an, Cain and Abel were the first and second sons of Adam and Eve, born after the Fall of Man (the only other child of Adam and Eve to be named in the Bible was Seth)

"In the course of time Cain brought some of the fruits of the soil as an offering to the Lord. But Abel brought the fat, fatlings, or milk as Josephus has it (the possible renderings of the consonantal Hebrew) from the firstborn of his flock. The Lord looked with favor on Abel and his offering, but on Cain and his offering he did not look with favor. So Cain was very angry, and his face was downcast. Then the Lord said to Cain, "Why are you angry? Why is your face downcast? If you do what is right, will you not be accepted? But if you do not do what is right, sin is crouching at your door; it desires to have you, but you must master it." Now Cain said to his brother Abel, "Let's go out to the field." And while they were in the field, Cain attacked his brother Abel and killed him."

- Genesis 4:3-8