hoever Cush was, (and there are a variety of theories), he obviously said some things that drove David to his knees. With intense intention David cried out to God for defense. Well, the introduction to this Psalm says that David sang these words. This would surely indicate forethought and contemplation. One doesn't spontaneously compose a song of this caliber on the fly. Psalm 7 isn’t ad lib. We see David's emotional connection to the words of Psalm 7, but he surely reflected deeply before bursting forth with this song.
He certainly began at a good place: "In God we trust!" (Psalm 7:1). And, this wasn't just an empty phrase from history. David meant it. He wasn't just trying to get out of trouble. In this melodic prayer, David said that if the accusations of his enemies were true, He prayed for God to execute justice on him. David was certain that Cush was an evil man who was just full of hot air.
We were introduced to David's imprecations already in Psalm 5:10. Here (in Psalm 7:6 & 9 particularly) David's sentiments in that arena are intensified. This shouldn't surprise us. David's view of God's vengeance juxtaposed against the despicable misbehavior of God's enemies (Psalm 7:12-16) would logically elicit the response that we find in verses 6 & 9. But, let's not get off track. David's primary objective was neither imprecation nor any form of self-justification. Psalm 7:17 indicates that what David really had in mind above everything else was praise. As David endured the words of Cush, he turned his attention to praising God. We should all follow suit.