No doubt there are heartfelt people in false religions. Some grew up in them, and they haven't yet seen that it does not match the bible. Catholics are encouraged to NOT read the bible, as it is distrust to the priest. First of all the bible says for each one of us to study to show ourselves approved unto God. And it is mentioned that some studied DAILY to see if what the apostles said was true. It did not say not to study because that shows distrust to the apostles. Second of all, the bible says we are all saints and priests in Christ. Each one of us has the responsibility to share the gospel with others.
When Jesus died on the cross He said it was finished? What was finished? He fulfilled the old law, He was the only one who could, and He nailed it to the cross. At the end of Revelation He also said it is finished. What was finished? The New Testament/scripture/His instructions to us- the bible was finished, and He said not to add to it or take away from it. But the Catholics did add to it. And the rules they added do not match what the bible says. For example, they say to pray to Mary. But the only way we, or our words, get to the Father is through the Son. Prayer is a form of worship, and Jesus says worship the Lord your God and serve Him only. He says cast ALL your anxieties on HIM (not her). If you cast some or all of your anxieties on her, you disobey God, cause He says cast them all on Him.
And the pope is trying to take Christ's place. Christ is the only head of His only body. He appointed elders and demons in individual congregations, but only He is the head of all the congregations. I was a child, but I remember seeing people bow down and worship him with my own eyes, and he accepted it gladly. But even as a child I refused to do so.