Ecclesiastes 11:9 in the King James Version
Rejoice, O young man, in thy youth; and let thy heart cheer thee in the days of thy youth, and walk in the ways of thine heart, and in the sight of thine eyes: but know thou, that for all these things God will bring thee into judgment.
Context
8 Yes, if a man lives many years, let him rejoice in them all; but let him remember the days of darkness, for they shall be many. All that comes is vanity.
9 Rejoice, young man, in your youth, and let your heart cheer you in the days of your youth, and walk in the ways of your heart, and in the sight of your eyes; but know that for all these things God will bring you into judgment.
10 Therefore remove sorrow from your heart, and put away evil from your flesh; for youth and the dawn of life are vanity.