De 8:1-20. AN EXHORTATION TO OBEDIENCE.

      1. All the commandments which I command thee this day shall ye observe to do, that ye may live--In all the wise arrangements of our Creator duty has been made inseparably connected with happiness; and the earnest enforcement of the divine law which Moses was making to the Israelites was in order to secure their being a happy (because a moral and religious) people: a course of prosperity is often called "life" (Ge 17:18; Pr 3:2).
      live, and multiply--This reference to the future increase of their population proves that they were too few to occupy the land fully at first.

JFB.