Ecclesiastes 6:12
For who knoweth what is good for man in this life, all the days of his vain life which he spendeth as a shadow? for who can tell a man what shall be after him under the sun? For who knoweth what is good for man in this life, all the days of his vain life which he spendeth as a shadow? for who can tell a man what shall be after him under the sun?
No one can determine by himself what is genuinely best for a person to pursue during this life. Human existence is brief and fleeting, passing like a shadow that does not remain. No one can foretell what will come after a person departs from under the sun. Human knowledge is therefore bounded on both sides, unable to settle life's true good and unable to discern the future.