They change the night into day: the light [is] short because of darkness.
Ver. 12. They change the night into day] i.e. My troubled thoughts render my nights restless, filling me with confusion. When the mind is unsettled the man cannot rest.
The light is short because of darkness] i.e. Comfort is long ere it cometh, and soon it expireth; Rara hora, brevis mora Rare the hour, short the delay (Bern.). The Vulgar, Post tenebras spero lucem, here, After darkness I hope for light (the ancient motto of the town of Geneva), is far fetched.