I am thus obliged in my own small way and from my understanding of it, to give an insight into this big question. Let us take this analogy.
A child is born into a family. At birth it cannot fend for itself; it cannot distinguish between its parents and complete strangers. But as it matures it begins to discern things around it. Soon it’s able to recognize its parents. It learns what is good for eating; learns to creep, walk, and run. It also learns to talk, and eventually begins to write and even solve arithmetic.
Soon, he leaves for boarding school, college or university to learn more. While there he may engage in different kinds of things, such as having his bath, washing his clothes, cleaning his room, eating, taking part in club activities etc. These things are important, no doubt, but are not the main reason for his being in school. While in school he has to learn those things which would also be of value to him when he has left school. Things which would be useful in another life…the life after school! These are the lessons taught in his field of study. If while in school he focuses much of his time on how well his room looks and gives very little or no time to these lessons, he may end up being useless to himself economically later in the life outside school. He therefore needs to put a lot more effort into his studies than on anything else. These other things only help to make life in school more comfortable or enjoyable. They are not the key to his future life. Hence no matter how badly he does them, if he performs very well in his field of study, he would still be assured of a bright future. But if on the other hand he does very well in these other things and performs poorly in his field of study, a better life outside might not be so assured. He would have squandered the time allotted to him for his studies and would therefore have to bear the consequences.
Now, as human spirits, we were not created here, but some place else…Paradise. That is our true home. Here on earth we happen to be in school; a school where we are supposed to learn those things which would be of value to us when we leave the earth and head back home.
In this school, through gradual development, we should eventually come to the recognition of God; to know and see Him as Creator of all things seen and unseen; as The Almighty God. We should come to know of His Power, and Grace; of His ways, of His Will…and adapt to them
Thus, as students on earth, we should learn to live a life of giving and sharing; a life of love; we should learn to make ourselves one with the Ten Commandments so that ultimately they become one commandment, the commandment of Love; loving God above all things and our neighbour as ourselves.
These are the lessons we take from here. Every other thing we engage in while on earth only helps us to absorb these lessons. Whether it is raising a family, work, social life etc, these things are in themselves of no value if at the same time we cannot through them learn to love each other; if through them we cannot adjust to a life free of envy, jealousy, avarice, greed, selfishness, covetousness, etc; if through them we cannot come to recognize the folly of a sinful life.
Simply put, using our earth life as school, we should learn how to live the heavenly life; a life that recognizes the value of love;
Ultimately therefore, through life on earth, we should come to recognize God…in His Love, Justice and Power.
Without imbibing these lessons, i.e. without knowing God, making ourselves one with His Will and adjusting to the kind of life lived in heaven, we cannot make it back home to eternal bliss in heaven.