The information that "Bathsheba had purified herself from her monthly period" relates to Jewish rules about hygiene (Leviticus 18:19), and it is significant on for two reasons. (1) It tells us that, because she recently had her period, she was not pregnant when she visited David. (2) It tells us that she was near her time of fertility. And it happened.

God confronts David about what he did. But He does it effectively, by getting David's attention with a story.

Can God forgive him?

However, the Lord still has a serious problem. The problem is the great damage that David did to God's reputation. David believed that the whole affair was a safe secret. But the truth was, everyone was gossiping about it. "Did you hear what David did?!" It is no different that what happens today when a highly respected Christian leader falls into immorality. And the unbelievers find the news most delicious. Nathan continued,

(1) Dealing with temptation

David's downfall started "innocently," with only a look. Who could have thought that look would lead to murder? The place David lost the moral battle was in the first temptation.

How should we deal with temptation? The Bible has a simple, clear instruction, in one word: FLEE! Run away from it.

And if you know in advance what you moral weakness are, and where those traps are waiting for you, don't go there! Alcoholics Anonymous counsels its members, "If it has been your habit to stop at the bar on the way home from work, don't even try to pass the bar without going in. You'll fail. Find another way home, so you don't even go near the bar."

We used to be able to counsel men who have moral battles of the mind, over lust, to get rid of the pornography in their homes, and to do their shopping only at stores which don't sell porn. But now we can get as much visual garbage as we can endure delivered fresh each day, through our cable TV movie channels and our Internet browser.

And in our conduct with other people and organizations, there is an old but true wisdom in this proverb:

(2)  God forgives.
No matter how great your offense, God still loves you, He forgives you, and He still can use you in His service.  This is precisely the reason Jesus went to the cross for you, so He could take eternal punishment for our sin and we wouldn't.    Let Jesus have it.  Let it go.
  

I close with a story from the autobiography of the late Senator Harold Hughes, The Man From Ida Grove. 

Before becoming a Senator, Hughes was Governor of Iowa.  Before that, he was a cussing, drinking truck driver, known to his friends as "Pack."  This story is from those truck driving days, a short time after he became a Christian

    As it takes a flame and wick to set off a powder charge, so do alcoholics suffer syndromes which start them drinking.  They find themselves in a situation where a combination of elements sets up a deadly desire.
    With me it was usually a lonely hotel room after a hard day's work.  No one would see me, and my family wouldn't know.
    Such a chain of elements was created when I checked in at the Savery Hotel in downtown Des Moines one night after a series of hectic business meetings.  Before leaving my room to go to a restaurant for dinner, I thought I'd relax for a moment.
    I had picked up a copy of the evening newspaper and was scanning the pages when I suddenly felt the urge.  By that time, I had not touched alcohol for over a year, and though there had been many urges I had been able to overcome them.  However, my longtime habit of an evening drink coupled with being alone in a hotel room generated a powerful force deep within me.  I wanted a drink. .I needed it.  I had to have it.
    Desperately I battled.  I turned back to the paper and tried to read.  Drumming incessantly within me, however, was the demand for a drink.
I stood up, the paper falling to the floor.  Suddenly, I felt like two different people, the new and the old Harold Hughes.  The urge became overpowering.  I knew that in a very few moments I would be going to dinner at a downtown restaurant.  To reach it I would pass an old drinking spot.  And I knew as well as I stood in that hotel room that I would go into my old haunt for a drink.  I could already savor its delicious burning strength.  I felt lost, defeated…
    I grabbed my coat from the back of the chair.  This is it, I figured.  Nobody's going to know about my getting drunk.  I'll just get it out of my system.
    In the exhilaration of decision, I pushed out the door and into the corridor of the hotel, heading for the elevators.  But as I stood waiting for the elevator, something came over me.  What was I doing?
    I leaned against the wall and prayed.  "Oh, God, please don't let me do this." The chime of the "down" elevator broke the spell and I headed for the open door.  The lust for a drink was in charge again.
    I strode through the hotel lobby out into a warm Iowa evening.  The traffic hubbub did not distract me from the neon lights of the bar down the street.
    One last spark of resistance flickered within and like a drowning man clawing, at a reed, I clutched a parking meter.
    "Pack!" Above the rumble of traffic I heard my name being called.
    I looked up and coming, toward me down the sidewalk was an old friend I hadn't seen in years.
"Imagine that!" he exclaimed, pumping, my hand.  "I step out of a cab and there you are.  What are you doing for dinner?" he asked.
    "I was on my way," I managed to say.
    "Well, come join me."
    As we walked together into a restaurant, I sensed a malevolent power leaving me.
    We had a good dinner, chatting over old times, and as we paid our bills, I realized the desire was completely gone.
    "Say," said my friend, looking up at me, a toothpick in his mouth.  "Wasn't that a coincidence, our meeting like this?"
    I thought of my feeble prayer at the elevator, and clapped him on the shoulder.  "No, Sam, no…  I     don't believe it was a coincidence at all!"

[Harold E. Hughes (with Dick Schneider), The Man from Ida Grove. (Chosen Books, 1979), pp. 114-116]