Eccl 3:9-15 – (9) What profit hath he that worketh in that wherein he laboureth? (10) I have seen the travail, which God hath given to the sons of men to be exercised in it. (11) He hath made every thing beautiful in his time: also he hath set the world in their heart, so that no man can find out the work that God maketh from the beginning to the end. (12) I know that there is no good in them, but for a man to rejoice, and to do good in his life. (13) And also that every man should eat and drink, and enjoy the good of all his labour, it is the gift of God. (14) I know that, whatsoever God doeth, it shall be for ever: nothing can be put to it, nor any thing taken from it: and God doeth it, that men should fear before him. (15) That which hath been is now; and that which is to be hath already been; and God requireth that which is past.
For the SIH devotional on this subject: