Rebbi Yaakov explains that a person should realize that the world we live in is only a preparation for the World to Come. Hashem didn't not create man for the purpose of this world but in order to receive the eternal reward in the World to Come. In order for man though to fulfill this purpose he needs to prepare himself accordingly by following the Will of G-d in this world. The Ramchal explains that it should be clear and evident to any thinking person that he was not created just for the existence of this world. He explains that most people don't have great lives in this world, they are faced with many struggles and hardships. Even if they are among the few that have everything good in this world how long will they live for ? 70 maybe 80 years and then they become like the dust of the earth. Contemplating this reality should bring anyone to the realization that the purpose of G-d creating man and giving him a soul is not for the purpose of the world we know. He therefore explains that man's true purpose is really for the world-to-come but in order to get there man must live and struggle through this world, the portico, in order to be able to enter into the palace. This world is our opportunity to prepare ourselves for our eternal destination, if we properly prepare ourselves now we will be able to reap the eternal reward for our work in the world to come.