I think that doing unto others as you would have them do unto yourself is a pretty self evident teaching by the Master teacher. However, the temptations of the devil have led man to rationalize to take advantage of one another and to put others down to exalt oneself. I believe all mankind is born with a certain degree of the light of Christ and basically want to do that which is right. But living among those who have chosen to ignore goodness and do evil deeds we tend to accept some of these worldly traits. It is important that we establish laws of goodness, justice, fairness, etc. among ourselves to be able to live as a community and society. The kingdom of heaven is a community or society of those who are willing to live by a higher and more loving law. God wants us all to be converted to living that higher law and wants us all to repent and forsake our evil ways. Those who learn to live and accept the higher law of the gospel will be able to enter the kingdom of heaven while those who refuse to live it will have to go to a lesser kingdom of which laws they are willing to obey. It is critical that we learn to live these laws of our own free will and choice. God will not force us to live his laws but will separate us to live in higher or lower kingdoms based on what we are willing to live by according to our own free will and choice. The punishment we receive is really brought upon us by our own free will and choice. The punishment is the regret when we realize the all that God has taught us was true and we didn't put our lives is order to live a celestial law. For us to truly be good beings, God knows that we must choose goodness of our own free will and choice. God has provided a way for us to gain forgiveness of our past sins and allows us to change into good beings. However, it is our free will to choose to do so or not. Those who are converted to doing good works are those who will receive the grace of God to enter into his kingdom where they are willing to live the higher law of goodness.