The aim of serving the Boreh Olam, Rabbenu Bachya teaches is, "For His sake alone,and they would comply with (His service) to draw near to Him." As we learned in the last paragraph, the same disciplinary actions that Rabbenu Bachya advises for father to child is what H'shem dictates to his people. "Promise of immediate rewards and threats of immediate punishment" This training would correct their understanding of reward and punishment in the world to come and bring them to desire to serve H'shem correctly as mentioned above.
pg 439
pg 439
