These 30 sayings have a certain similarity or loose comparison with the Egyptian Instructions of Amenemope with its 30 chapters from around 1300-1075 BCE. They sayings are about admonitions and knowledge. They intend to show you what is right and true. That way, you can answer anyone who sent you. These sayings are more international in tone.
The rebellious kings were warned to fear Yahweh and his king. They should be wise. They have been warned. All rulers should have fear and trembling before Yahweh. They were to kiss his feet. Yahweh did not have feet, but his King David would have feet. If you got Yahweh angry, you would perish because he was quick to anger. However, those who took refuge in Yahweh would be happy and blessed. Thus we have a royal psalm about Yahweh as the real national and international king. However, he wanted his son David, and by extrapolation, a future king, the anointed one to be king of the earth. Anyone who got in his way would be in trouble. Yahweh was quick to anger and ready to destroy if he saw fit.