Imagine for a few minutes that there is no such place as Hell. Imagine that the most saintly people and the most despicable members of society had no punishment after death, and that everyone had eternal life and was joined with God. Imagine that there was no place to be saved from, and the purpose of life was only to have experiences in the physical world. If there was no Hell, would you act any differently? How do your actions now reflect on yourself? Do you find yourself fueled to not sin because you are trying to gain an award or because you are trying to avoid punishment?
If there is no hell, there is no justice - inasmuch as at least one person with enough resources can commit a heinous crime and go unpunished, or even worse, enter a state of eternal joy despite his wrongdoings.
If there is no justice, I can do what pleases me most, according to the maxim “might makes right”.
I have no reason to embrace sorrow and suffering on behalf of others, no reason to give up pleasant things in order to become a better man, no reason to sacrifice my life for someone in need.
I have no reason to fight or reduce criminality or injustice, no reason even to condemn injustice.
In fact, in the certainty of an afterlife with everyone in heaven no matter what, an eternity of bliss no matter what, I would put an end my life immediately.
Do you realize how flawed, in fact how dangerous this idea of yours is? I sure hope so.
The only difference between this and atheism is that an atheism doesn’t believe in heaven either, so he doesn’t take the last step in my reasoning, but could potentially adopt the previous ones, not caring about anything but himself, maximizing his gains and pleasures as long as he can breath. And many do so.
Christians, especially Catholics, are meant to be the opposite: to live for our brothers and to love God above all else and everyone, friend or enemy, family or stranger, just as God loves us. To embrace sacrifice and reject lust, vanity, and pride, not for a reward, but out of love…for the greater glory of God and for the salvation of souls of our brothers, many of whom don’t know Christ and His Church, or don’t even know God at all.