In the Bible, Abel and Cain are the first two sons of Adam and Eve. Both gave sacrifices to God. God favored Abels more then Cains. Out of jealousy, Cain murdered Abel. The song is trying to sample that but in this time, “ Innocent, you’re standing all alone, So how do I have the nerve to call you in front of my friends?” this is like some people favoring other people than other ones so they “make fun” of them.