Abe is the second son of Adam and Eve, who was slain by his older brother, Cain (Genesis 4:1-16). Abel, a shepherd, offered the Lord the firstborn of his flock. God respected Abel’s sacrifice but did not respect that offered by Cain. In a rage, Cain murdered Abel, then became a fugitive because of the curse placed upon the ground (a curse of infertility) onto which Abel’s blood had spilled.
Genesis makes the point that divine authority backs self-control and brotherhood but punishers jealousy and violence. In the New Testament the blood of Abel is cited as an example of the vengeance of violated innocence (Matthew 23:35; Luke 11:51).
Taken from Merriam-Webster Encyclopedia of World Religions 1999