1. The title to this psalm (which was not original and about which we cannot at all be certain) is puzzling. What was a "shiggaion"? Who was Cush the Benjamite? Perhaps the obscurity of the title speaks to its historicity. Nothing about the content would speak against David as its author.
2. Psalm 7 might be called an imprecatory psalm in that it asks God to judge the psalmist's enemies. It asks the LORD in anger to rise against the fury of the psalmist's enemies (7:6). The sense of verse 7 is unsure, but it may ask God to take his seat in judgment over an assembly of peoples. The psalmist asks the LORD to bring the evil of the wicked to an end (7:9).
3. For the psalmist's part, he is turning to the LORD for refuge, as his enemies try to drag him away like a lion (7:1-2). The psalmist believes he is innocent. If he is truly guilty, he says, let his enemies prevail (7:3-5). He gives examples of the kind of thing that would make him guilty--repaying a friend with evil or plundering an enemy without cause (7:4).
4. We have an interesting picture of God in this psalm. God is righteous and just (7:9). He judges the hearts and the kidneys (metaphorical seat of the intention). He is angry (at evil) every day (7:11). When someone does evil, he sharpens his sword, strings an arrow, bends his bow (7:12). He has deadly weapons, flaming arrows (7:13). But for the psalmist he is a shield (7:10).
5. The evil make a pit and then fall into it (7:15). Their mischief falls on their own heads (7:16).
The LORD gives wisdom. This is exactly what James says (1:5). His wisdom is for the upright. His understanding is a shield to them. Wisdom, knowledge, prudence--they all watch over a person. They guard a person. They save from the way of evil. Wisdom saves from the crooked, from those who rejoice in doing evil, from the devious.
Psalm 1 and Proverbs 1:1-7
Psalm 2 and Proverbs 1:8-14
Psalm 3 and Proverbs 1:15-19