There are 4,200 different religions in the world today and no, they do not all worship the same god. A popular theme among belief systems is some form of afterlife often distinguishing between rewards for the faithful and punishment or rejection for the unbeliever. If such a common theme turns out to be inaccurate then your choice of religion or lack thereof will have little significance. However, if there is a heaven and hell and our destination depends entirely upon the decision we make today then we need to be absolutely certain we make the right choice.
While most religions hold to this idea of a reward / punishment scenario, they do not agree on how to achieve the reward and avoid the punishment. Out of all the possible religious choices, Christianity stands apart, unique in its approach to both life and death. While we cannot compare all religions since there are simply too many, we will take a brief look at the five largest religions and compare their views on eternity.
Hindus teach the laws of karma. They believe their situation in this present life is a direct result of their actions in a previous life. Punishment or reward is gained through reincarnation. If you are poor, malnourished, neglected, or abused, it is not because someone abused you or deprived you of food and shelter, no, it’s because of your karma. You must endure punishment for your sins in a previous life and if I were to help you by giving you food, clothes, a job, shelter, etc, I would actually be harming you because now you are not receiving the punishment you deserve and you must now continue to suffer in your next life because you were aided in this life. To be free from karma you must endure punishment for previous sins while you work toward spiritual perfection. There are three possible ways to end this cycle of karma: 1. Be lovingly devoted to any of the Hindu deities; 2. Grow in knowledge through meditation of Brahman (oneness)...to realize that circumstances in life are not real, that selfhood is an illusion and only Brahman is real; 3. Be dedicated to various religious ceremonies and rites.
In the new age belief system, you are a god, and so am I. Everyone is a god. As a god, you are the originator, controller and power over all that is around you. There is no reality outside of what the reality you determine. Nothing in your life is wrong or evil. How can it be when you are controlling your reality? Negativity and ultimately reality itself is an illusion. You must develop your spiritually to the degree that there is no objective, external reality. A person, becoming a god, creates their own reality. And after death you have your choice of a new plane of existence or reincarnation, likely dependent on the degree to which you were able to empower your inner godhood and spirituality. You are on your own, striving for spiritual perfection.
Buddhist also believe in reincarnation but they do not hold claim to any god. This world is mired with hardships, sickness, tragedy, sadness from which there is no escape not even in death, thanks to the inevitable rebirth of reincarnation. All these rebirths mean that no one is ever free from suffering. A Buddhist seeks to end these rebirths, to be free from suffering by not returning to a world of suffering. They believe there are three things which draws us back into this life, three things which must be severed if we are to be free from the cycle of rebirth. Buddhists believe it is a person's cravings, aversion and delusion that cause these rebirths. Therefore, the goal of a Buddhist is to purify one's heart and to let go of all yearnings toward sensual desires and the attachment to oneself. One must extinguish the fires of attachment, and ignorance. By following the Noble Eightfold Path you start with extinction of the three fires (passion, hate, delusion), proceed to ceasing all discursive thoughts and apperceptions, then ceasing all feelings (happiness and sadness) unto nothingness, which leads to nirvana. Nirvana is not heaven or a blissful paradise. Nirvana is the complete cessation of everything, including consciousness and rebirth. Nirvana is the escape from the suffering of life into nothingness.
Muslims believe there is one god named Allah and they are his servants. To be a Muslim, one must follow five religious duties: 1. Repeat a creed about Allah and Muhammad; 2. Recite certain prayers in Arabic five times a day; 3. Give to the needy; 4. One month each year, fast from food, drink, sex and smoking from sunrise to sunset; 5. Pilgrimage once in one's lifetime to worship at a shrine in Mecca. At death a Muslim will be judged by Allah based on one's faithfulness to these duties a Muslim hopes to enter Paradise. If not, they will be eternally punished in hell. A sure way to guarantee acceptance is to give up ones life for Allah (jihad, for example). Good deeds and disciplined religious rituals are considered essential to enter paradise and even with these some Muslims will find themselves unworthy. Even the guaranteed entrance of jihad is still something one must do to prove themselves worth of acceptance by Allah. For those outside of Jihad, how will you ever know for sure that you have done enough to gain approval?
Christianity believes in one creator God who dearly loves each aspect of His creation. Humanity chose to disobey God and to try to find their own way, a decision which resulted in death and sin. Since the time of Adam and Eve mankind has been looking for a way to gain favor with God on their own terms, but while God is love He is also just and cannot accept anyone guilty of sin. To be sinless one must be pure of heart, thought and action from the moment of conception until the moment of death. Any selfish act, even as a toddler, any pride even in our thoughts, condemns us to an eternity in hell. God is holy, sinless and pure and those who follow Him must also be holy, sinless and pure. We try to earn God’s favor through good deeds and religious rituals to the true God and to the various gods of our imagination, but our hearts are full of sin so our actions and sacrifices are tainted with it and unacceptable. We cannot work our way up to heaven, so God came down to earth. God came to earth as a man named Jesus, born of virgin in Bethlehem. Jesus lived a life without sin but paid the penalty for all sin by His death on the cross. We cannot earn salvation, but God gives salvation freely if we simply say yes to Jesus.
In short: Hindus = You must perform ceremonies and realize spiritual truth. New Age = You overcome reality and create your own reality. Buddhism = you must let go of all desires and attachments to become nothing. Islam = You must perform the five pillars and participate in Jihad. Christianity = God saves you, you just need to let Him.
Perhaps Billy Graham explained it best:
There are many religions in the world, but only one Christianity, for only Christianity has a God who gave Himself for mankind. World religions attempt to reach up to God; Christianity is God reaching down to man”