Thematic Bible: What is not vain

and Moses finisheth to speak all these words unto all Israel, and saith unto them, 'Set your heart to all the words which I am testifying against you to-day, that ye command your sons to observe to do all the words of this law, for it is not a vain thing for you, for it is your life, and by this thing ye prolong days on the ground whither ye are passing over the Jordan to possess it.'