Deuteronomy 32:46-47

KJV_Strongs(i)
  46 H559 And he said [H8799]   H7760 unto them, Set [H8798]   H3824 your hearts H1697 unto all the words H5749 which I testify [H8688]   H3117 among you this day H6680 , which ye shall command [H8762]   H1121 your children H8104 to observe [H8800]   H6213 to do [H8800]   H1697 , all the words H8451 of this law.
  47 H7386 For it is not a vain H1697 thing H2416 for you; because it is your life H1697 : and through this thing H748 ye shall prolong [H8686]   H3117 your days H127 in the land H5674 , whither ye go over [H8802]   H3383 Jordan H3423 to possess [H8800]   it.