The arrow can't make him flee. Sling stones are like chaff to him.
Referenced Verses
Job 39:7 : 7 He scorns the tumult of the city, Neither hears he the shouting of the driver.
Hab 1:10 : 10 Yes, he scoffs at kings, and princes are a derision to him. He laughs at every stronghold, for he builds up an earthen ramp, and takes it.