A Psalm of David, when he fled from Absalom his son.
 O LORD, how many are my foes! Many are rising against me;  many are saying of my soul, “There is no salvation for him in God.” Selah (ESV)
Have you ever felt like the whole world was against you? You are not alone in that feeling. David writes this Psalm at the very time when he is fleeing for his life from his own son, who was trying to steal the kingdom away from him. King David was a man after God's own heart. He was the standard by which all kings of Israel were measured against. Yet, he had to deal with betrayal and heartache in his own family.
It's interesting to note that David's foe was primarily Absalom. Yet, he says that his foes are many. It does not take many people to be against you for it to feel like an overwhelming number. Just a few people who are willing to stir up trouble against you can feel like an army. Just a few words that are filled with poison can have amazing effect. Here is an example of just one man who said poisonous words to David during this terrible time:
2 Samuel 16:7–8
 And Shimei said as he cursed, “Get out, get out, you man of blood, you worthless man!  The LORD has avenged on you all the blood of the house of Saul, in whose place you have reigned, and the LORD has given the kingdom into the hand of your son Absalom. See, your evil is on you, for you are a man of blood.” (ESV)
These words were not true. The Lord never gave David's kingdom to his son Absalom. But, words do not have to be true to be hurtful. As David writes in this Psalm, "many are saying of my soul, “There is no salvation for him in God." False accusations. Hurtful words. The feeling that the whole world is against us and there is no hope. We go through this in our lives as well.
If you are struggling with betrayal and false accusation be encouraged. You are not alone. And if you are allowing yourself to treat someone with contempt and even false accusation, repent. Do not be a part of someone else's destruction.