I will sing of your love and justice; to you, O LORD, I will sing praise.  I will be careful to lead a blameless life – when will you come to me?  I will walk in my house with blameless heart.  I will set before my eyes no vile thing.  The deeds of faithless men I hate; they will not cling to me.  Men of perverse heart shall be far from me; I will have nothing to do with evil.”

It sounds to me like David is setting himself apart from the world.  Even though he must live among sinful men, he wants to be identified, not by faithlesss works, slanderous words or deceitful men, but rather his identity will be that of a man who loves and praises God’s justice, God’s love.

As God’s children, sealed by the blood of Christ, this should be our identification as well.