We Reap What We Sow

2 Samuel 12:10
“Now, therefore, the sword will never depart from your house, because you have despised Me and have taken the wife of Uriah the Hittite to be your own.”

This is an uncomfortable passage. To hear the Word of the Lord against us. The lesson is we will reap what we sow. If we sow sin and selfishness, we will gain bitterness. The tough part of this is that this taints his family. 
God is still merciful in this. God isn't sending David to hell, but there will be consequences to his actions. Not all in his family will have this curse. 
What can David do? He needs to be careful not to drift into sin as before. He prayed the right prayer in Psalm 51:10, "Create in me a clean heart, O God, and renew a right spirit within me." He needs to keep that sense of vulnerability. To lose that opens a door to sin. 
David also can't focus on the horrible act and the consequences. They are too bitter. Keep the lesson. Know what we are capable, but don't obsess over it. God and His mercies are our focus. Here are a couple of bible passages that tell us where our attention should be: "Set your minds on the things above, not the things on the earth", (Colossians 3:2). And "Finally, brothers, whatever is true, whatever is honorable, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think on these things", (Philippians 4:8). 
The Kennedy's are a family that were sinful and reaped the result of sin. The Grandfather was involved in illegal activities. It appears their fortune was built from it. It's been said that JFK was elected on corrupt actions. It's tragic to hear of all the violent deaths in that family. 
Lord, thank You for the warnings. Help us to avoid evil. Thank You for David and the many lessons we learn from him. Thank You that You showed him mercy. Help us to avoid sin.