The prophet Nathan had a problem.
King David had done a pretty awful thing. Having seen the wife of Uriah the Hittite, Bathsheba bathing on a rooftop, he had wanted her and taken her in adultery. She became pregnant as a result.
This was awkward because Uriah was in the fields, at war. Her pregnancy could not be merely explained as the natural occurrence of normal marital relations.
When she informed him she was pregnant, David brought Uriah back from the battle front to spend some time with him. He suggested to Uriah that he profit from the trip to "wash his feet" (in other words, spend some "time alone" with his wife) in order to have a convenient excuse for her pregnancy. For reasons of faith and custom, and being a loyal soldier and valuing his King and his God before all, Uriah refused, so David had simply sent a fatal message back with him to the general Joab - that Uriah was blissfully unaware of - that Uriah be moved out into the hardest fighting, and then literally abandoned to die. David betrayed a good friend twice, and Uriah died alone in a forest of enemy swords.
With Uriah slain, David took Bathsheba as his wife.
The only ones to know of this horrible treachery were Bathsheba, David, and Joab.
Or so he thought.
Nathan had to tell David that there would be awful consequences of these actions, and that David would probably not want to hear this message. After all, as far as David knew - Uriah was dead, and none would be any the wiser as to when the pregnancy took place - so the news David was to hear would be particularly galling.
So Nathan started out with a story about a poor man and a rich man. When a traveller came to town, the rich man didn't take an animal from his own herds, but instead stole the only thing of value to the poor man: a lamb which was a treasured family pet - so much so that it ate from the family table and slept with the family. The animal that was like a daughter to the poor man was cooked and eaten for the benefit of a traveller.
David was so enraged he said "As God lives, this man must DIE."
And Nathan's response was bone chilling: "you are the man."
There's a lot that can be read from this story, and so many things can be preached about it. Adultery. Treachery. As ye sow, so shall ye reap. For those who want to know "the rest of the story", Nathan's following proclamations are even worse. David will not die, as he declared should happen to him - but it's an awful kind of mercy, as he lived enough to not only see the agonizing fevered death of the child, but the fact that there will be a sword against his house for the rest of his days. His wives will sleep with a member of his own household on the rooftop and he will be publicly cuckolded.
This came true with Absalom - who started things off by raping his half sister. His own son Absalom would later sleep with his concubines to demonstrate his usurping of his father in a civil war, one which Absalom eventually loses: David learns of his son's death and wishes he himself had died.
We very rarely get the opportunity to stand outside ourselves and judge ourselves objectively. We rationalize our own decisions and try to justify our own sins.
It's clear when faced with an objective viewpoint on our actions, we're insanely fast to judge the actions and to be harsh to those who do what we ourselves would do. In fact, it's one of the reasons why homosexuality is condemned so often from the pulpit and not adultery, even though it's the latter that is in the Ten Commandments - because most would never see themselves in the arms of another man (or another woman) but know full well that despite all proclamations to the contrary, there's that dark thought that we're all a few drinks, an angry fight, a slammed door and some lonely months away from doing what we say we never would.
For a more modern example, one has only to look at Rush Limbaugh, who famously and very publicly proclaimed that drug addicts were complete and total moral failures. I won't go into what else he said about the situation, but suffice it that when he himself was arrested and very publicly humiliated - not only for drug crimes but for blackmailing and putting others under duress to commit crimes to obtain drugs for him - he had nothing else to say but to admit yes, he had an illness. It was an illness. He had been wrong.
It's why Jesus taught over and over again that compassion and forgiveness are paramount in life. No, they aren't license to commit sins - as the story of David and Bathsheba shows, salvation and forgiveness cannot change the past nor can they shield you from the horrible consequences of your actions - especially when those consequences affect third parties you're impotent and powerless to save. In fact, as Nathan was iterating through the devastating ripple effects of David's actions, he leads off with the startling preface that God has already forgiven him his sins - the story is more to illustrate that God's forgiveness doesn't change the natural laws of the universe and that there are reasons outside of your soul's final destination to stay on the right path.
But imagine that split second, shifting-gears-without-a-clutch moment in which David goes from wanting to kill someone over the death of an animal, to praying fervently to God to be spared the consequences of his own murder. We all will have days like this. We should remember them in "peace-time" and meditate on the very real reasons we shouldn't judge ourselves or each other too harshly - because it can blind us to what really matters - our actions and their consequences.