During formation, someone asked what makes Catholicism special if anyone can go to Heaven, regardless of their religious beliefs. Father seemed to struggle with a solid answer to that question. It is a hard concept to grasp without landing in a relativistic mindset.
We are all born with the knowledge that there is a God and we are meant to be with him in Heaven. God set up a distinct path that leads anyone who follows it to Him. But, we are flawed people. Some refuse to acknowledge that God exists, let alone a way to reach Him. Others try to create their own path believing that as long as it feels right to them, they must be on the right path. Then there are still others that want to be on the path, but loose their way. A very few are able to not only find the path, but stay on it. Those are the people who make it to Heaven.
Every religion believes they have the map that shows the path, but only our map was given to us directly by God. It the most complete and accurate map available. Those who choose to follow God's map have a full proof way into Heaven. Yes, they will stumble and fall off the path at points along the way, but ultimately they will get to where they are trying to go. The rest of us, those who aren't saints, will have a much harder time keeping to the path. We have the ultimate map, but we forget to look at it or think we have it memorized or we're pretty sure there's a short cut just over the next hill. Some of us will make it to Heaven despite our failings and others won't.
All other maps are incomplete or inaccurate. It may lead people on the correct path for a while, but goes in the wrong direction at other times and never quite leads to Heaven. They may see the road signs that tell them they are going the wrong way, but give them no thought or refuse to believe what they know in their heart. A very few will follow that call from God that is ingrained in every heart and they will be led on the right path.
As Catholics, we need only to pull out the map and follow it.