Job complained about the brevity of human life by declaring that his days went by faster than a swift runner. He was probably referring to the fleet-footed messengers used by Old Testament kings to carry important messages to distant places.

King Hezekiah of Judah restored several important religious practices, including observance of the Passover, which had been neglected by the people. He sent “post [couriers, NIV]. . . with . . . letters. . . throughout all Israel and Judah” (2 Chronicles 30:6), summoning all citizens to gather a Jerusalem for this solemn occasion.
JOB 9:25- My [Job’s] days are swifter than a post [runner, niv]: they flee away, they see no good.