This is a common question in response to my position on salvation theology, that non-Christian believers and unbelievers can be saved by love of neighbor and invincible ignorance. Several points are key in understanding why it is better to be a Catholic than a non-Catholic Christian, a non-Christian believer, or an unbeliever.
1. The path to Heaven is easiest for believing and practicing Catholics.
We have all seven Sacraments. We have Confession to return us to the state of grace, even if we have only imperfect contrition. We have many more graces through the devotions and prayers of the Church. By greater grace, our path to Heaven is made easier.
2. We more easily avoid actual mortal sin, and more easily repent.
We have the teachings of the Church on faith, morals, and salvation. It may seem, from a worldly point of view, that having the fullness of the eternal moral law taught to us is more restrictive, making our path harder. But that is not the truth. Rather, by conforming our lives to the fullness of the moral law, we more easily avoid grave sin and more easily repent if we fall. By comparison, other believers and non-believers, who might fall into mortal sin with a sincere but mistaken conscience, have less grace and so they have a more difficult time avoiding the sins that are not beyond their poorly informed conscience, and a more difficult time finding the path of repentance.
3. We have greater glory in Heaven.
Having cooperated with grace more often and more thoroughly, believing and practicing Catholic have much greater glory and happiness in Heaven forever. A sinner who commits many objective mortal sin, even without the full culpability of actual mortal sin, has less glory in Heaven.
4. We have greater happiness on earth.
For we are consoled by grace and providence and truth. For we know that our true home awaits us in Heaven.
5. We are able to help very many souls to also reach Heaven.
By comparison, an atheist or a believer in a non-monotheistic religion offers much less help, and perhaps offers much harm, to the path of salvation of other souls.
So it is better to be a believing and practicing Catholic than to be a member of any other religion, or to be an unbeliever.
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