In the Garden of Eden, Satan enticed the woman to eat that which the Lord God had forbidden – the only fruit God said not to eat.  Her husband knowingly ate it and immediately both knew true guilt – the guilt of sin against God and what He had told them. 

(NASB) Genesis 3:1-7 “NOW THE serpent was more crafty than any beast of the field which the Lord God had made.  And he said to the woman, ‘Indeed, has God said, ‘You shall not eat from any tree of the garden’?”
2  The woman said to the serpent, ‘From the fruit of the trees of the garden we may eat;
3 but from the fruit of the tree which is in the middle of the garden, God has said, ‘You shall not eat from it or touch it, or you will die.’”
4 the serpent said to the woman, ‘You surely will not die!
5 “For God knows that in the day you eat from it your eyes will be opened, and you will be like God, knowing good and evil”
6 When the woman saw that the tree was good for food, and that it was a delight to the eyes, and that the tree was desirable to make one wise, she took from its fruit and ate; and she gave also to her husband with her, and he ate.
7 Then the eyes of both of them were opened, and they knew that they were naked; and they sewed fig leaves together and made themselves loin coverings.”

  After their sin, they did know good and evil.  They were guilty and both knew it.  Why else would they make coverings for themselves?
  Guilt of sin is known, it is experienced by everyone who knowingly does what God has expressly forbidden.  Such as sexual promiscuity, abortion, or whatever comes to your mind through your own experiences.

  Adam and Eve used fig leaves to cover their nakedness – what do you use to cover your nakedness before God?