If you were never a Catholic and trying to witness or dialogue the Gospel to Catholics, you must put yourself in their shoes in order to be effective and also so they do not turn their ears off to you. These are some of the key points you must understand of their mindsets.
1. Most if not all modern day Catholics view the “church” as Catholic vs Protestant. Since Vatican II, the mindset has changed in that they will deem some Protestants as the same, as long as they have been baptized and are not attacking RCC doctrines or if they are currently practicing ecumenism with the RCC. They do not view the church from the Gospel or as born again believers added to the body of Christ, but from an organizational-institutional ideology. They view the “church” as to where you “go to church”.
2. A “Protestant” is every non-Catholic Christian to the Roman Catholic. Doesn’t matter if you don’t attend a classical Protestant church, they will deem you has a Protestant. They basically believe your faith was invented in the 16th century by Martin Luther, and not granted by God as Scripture states, as they don’t even see their own faith granted by God. They view the total actual substance of faith as being passed down from others, thus their mindsets are totally different in this regard. Where as faith is only passed down as a witness and testimony, it is granted by God to personally believe, His work on the sinner’s heart, it is not self actuated.
3. They are led to believe that Martin Luther removed books from the Bible, so the 66 book Bible has missing books. Nothing could be further than the truth. It was the RCC who ADDED books as “inspired” Scripture to their canon in the 16th century in response to Luther’s Reformation. Luther did not remove any books. He just didn’t add the Apocryphal books to the canon as Jerome the great RCC Latin translator did not add these 7 books to the canon of the Bible. But deemed them as “extra” or “added” books, not inspired by God as the church had always done.
4. They view the RCC as the originator of the Bible, they totally believe it was the RCC who “compiled the canon”, that they were in effect the author of the canon, not God. That the actual Bible just came into existence in and around the 4th century via their help alone. So with this, their mindset gives a license to absolutely ANYTHING the RCC ever taught and teaches. Challenge this point that God is the Author of His canon, and their whole ideology will start to crumble, so is why they fight extra hard to defend this notion. The Roman Catholic mindset is highly agnostic when it comes to God’s Authorship and Canon.
5. They do not view their extra attention and focus to Mary is idolatry or worship of her. They view it as “honoring Jesus’ mother”. The RCC has given full license for this hyper focus of Mary as the Catholic is led to believe that she knows them personally and can hear their prayers. A RCC convert will shy away from Marian doctrines where as a cradle Catholic (infant baptized) is much more eager to embrace them openly and without any hiding their belief Mary is working on their behalf.
6. They are under a guilt system. They MUST attend Sunday Mass and every unbiblical holy day of obligation throughout the year, or the RCC places a “mortal sin” on them, meaning unless they confess and receive forgiveness through their sacrament of Reconciliation, missing a Mass puts them in danger of hell fire. There is NO reliance on the Holy Spirit, nor can they clearly translate His work in their life.
7. They view Scripture as an authority, but NOT the only authority for faith and practice. RCC tradition and the magisterium have equal authority in their mindsets. This would be where the MAIN disconnect they will have with your witness of the Gospel to them as they see tradition and their magisterium’s teachings on equal par with Scripture. They despise a non-Catholic’s ability by the Holy Spirit to interpret the systematic context of Scripture, this is an alien concept to them.
8. Since Scripture is NOT their ultimate authority for faith and practice, they can ONLY read Scripture by what is called eisegesis. In effect, they use RCC tradition and the magisterium more so and READ INTO Scripture what is taught by these two authorities in their mind. A Catholic for example will read INTO John 3:16, the most quoted verse, that Mary is in that verse somewhere.
9. They are required by guilt to WORK for their salvation. After initial justification which they say comes through RCC baptism by grace and mercy alone, they then are required to maintain and/or keep their justification standing with God by their works. This would be participation in the sacraments, works of charity, etc. They do not believe in being saved FOR good works, as a resultant evidence of salvation, but works are needed to GAIN salvation in the end and KEEP their salvation.
10. No Catholic can truly say they have been saved to the uttermost here and now. They are taught uncertainty so they continue to work for their salvation. They really don’t know where they will end up when they die, they hope for purgatory, an after death sin cleansing fictional place. One day a Catholic can feel saved, the next day not so much, and on it goes. They DO NOT BELIEVE they are saved FOR good works, but BY their “good” works.
11. They view their faith as “between myself and God”. Hardly if any Catholic will have a personal testimony and witness to share in Jesus Christ. They do not evangelize sinners by the Gospel, they only try to possibly convert them to Catholicism. The actual Gospel is void in a Catholic’s mind, so don’t expect a clear answer if challenged on what the Gospel is. One cannot share the Gospel if they have NOT been saved by it, and Catholics are a CLEAR example of this fact.
12. There is a certain block in their mind to the Gospel. Things like “place your faith alone in Jesus Christ” is utterly resisted, it is not accepted, they revile at such a notion because it eliminates the others in the equation they are led to believe are there, such as Mary, the dead RCC saints they believe are working on their behalf, and their works.
If you were under the impression that Roman Catholics are Christians, that they just need a tweeking of what they believe, I ask you to ABANDON that thought! They like every unbeliever needs the Gospel of their salvation shared with them. The RCC is arguably the largest mission field sitting in your backyard, so do not ignore them, do not buy the externalities of a religion, do not bend or appease their false gospel and mindsets. Share the Gospel BOLDLY to them!