Got very distracted by it being a Shiggaion. Apparently it refers to it being a wandering or even wobbling or perhaps drunken song! Its very don’t in theme. The term probably describes the music style. Spurgeon found wandering in the theme, but I think that’s stretching it… It’s pretty focused.
The reference to cush the Benjamite seems to be a palace intrigue… He was poisoning David’s reputation to the king (Saul).
So it’s like a rant about a bad work situation, though at a life and death level, as we know it became.
He asking the lord for refuge and somehow comparing his pursuers to a lion that will get him apart takes you right into how immediately terrified he is, it’s very personal and human.
The next section could seen like bragging, about how good he is, though giving him the benefit of the doubt it could also be deep soul-searching introspection. He really can’t see he’s done anything near as dastardly as his attackers.
God is the most significant relationship in his life. If his attackers win, it will be god’s doing. Though ostensibly a prayer to god about an immediate threat, as so often in davids writing, the threat becomes a bystander to the real drama and journey of David’s relationship with God.
Then God gets bigger still. Rise up, he says, and judge but he’s not petty. Judge them, judge me, judge the world! It ends with a general call to repentance.