There is none that understandeth, there is none that seeketh after God. The Biblical account of man's historic fall out of a state of righteousness and holiness into a state of sin and condemnation explains the dark side of man. People lie, cheat, steal, murder and rape because they are sinners by nature . Sin is a power that came into the world through Adam's disobedience. It's simply disobedience to God's Word.
Sin rules the world, enslaves and controls people.
It's effect on all mankind is separation from God. Therefore, in order to be reunited with God, we must be cut off from sin and set apart to righteousness. If we are to approach and be reconciled to God, we must do so on God's terms - we must have new lives in which our sins have been completely forgiven and obliterated. Scripture tells us that we cannot save or redeem ourselves. Sin can only be overcome by a sacrifice.