What Catholics believe and where we agree

What you'll learn

Identify the core doctrines Catholics and Protestants share and the points where the Reformation divided them
Explain the Catholic structure of authority (Scripture, Tradition, Magisterium) and the sacramental system using the Catechism's own paragraphs
Distinguish official Catholic dogma from popular piety, and describe a respectful, gospel-centred way to open a conversation with Catholic family and friends

Real common ground

Start with what is true. The Roman Catholic Church confesses the Apostles' and Nicene Creeds. It teaches one God in three persons, the full deity and full humanity of Christ (two natures in one person, what theologians call the hypostatic union), his virgin birth, atoning death, bodily resurrection, ascension and future return in judgment. It affirms that Scripture is inspired and without error. On these points a Catholic and a Reformed Christian stand together against Jehovah's Witnesses, Mormons, Muslims and secularists.

This matters for how you talk. A Catholic friend is not an unbeliever in the way an atheist is. Many Catholics truly trust Christ, sometimes in spite of what their system teaches. Our disagreement is not over whether Jesus is God but over how his saving work is applied to sinners, and who has authority to say so. Those are not small questions. The Reformers believed the gospel itself was at stake. But we begin by naming shared ground honestly.

What real common ground do Catholics and Reformed Christians share, and where does the real disagreement lie?Show answer

The Catholic Church confesses the Apostles' and Nicene Creeds: the Trinity, Christ's full deity and humanity, virgin birth, atoning death, bodily resurrection and return, and the inspiration and inerrancy of Scripture. On these points Catholics and Reformed Christians stand together against other religions and secularism. The disagreement is not over whether Jesus is God but over how his saving work is applied to sinners and who has authority to say so, which the Reformers believed put the gospel itself at stake.

shared creeds and Trinity
Christ's person and work affirmed
Scripture inspired
disagree on applying salvation and authority

Scripture, Tradition and Magisterium

Catholicism has a three-legged structure of authority. Scripture is the written Word of God. Sacred Tradition is the Word of God handed on orally from the apostles through their successors. The Magisterium is the living teaching office of the Church, the pope and the bishops in communion with him.

Vatican II's constitution Dei Verbum (1965) says Tradition and Scripture flow from 'the same divine wellspring' and that both are to be accepted and venerated 'with the same sense of loyalty and reverence' (DV 9). It adds that the teaching office 'is not above the word of God, but serves it' (DV 10). The Catechism repeats this: Tradition and Scripture are bound closely together (CCC 80), the Church 'does not derive her certainty about all revealed truths from the holy Scriptures alone' (CCC 82), the task of authentically interpreting the Word belongs to the Magisterium alone (CCC 85), and the three are so linked that 'one of them cannot stand without the others' (CCC 95).

Notice the practical effect. Even though the Magisterium claims to serve Scripture, in practice the Magisterium tells the Catholic what Scripture and Tradition mean, and nothing can correct it. That is the root disagreement behind every other one.

Explain Catholicism's three-legged structure of authority in your own words, and why it is the root of the other disagreements.Show answer

Scripture is the written Word of God, Sacred Tradition is the Word handed on orally from the apostles through their successors, and the Magisterium is the living teaching office of the pope and bishops. Dei Verbum and the Catechism say Scripture and Tradition are to be honoured with equal reverence and that authentic interpretation belongs to the Magisterium alone. Even though the Magisterium claims to serve Scripture, in practice it tells Catholics what Scripture and Tradition mean, and nothing can correct it, which is the root of every other disagreement.

Scripture, Tradition, Magisterium
equal reverence (DV 9)
Magisterium alone interprets (CCC 85)
nothing can correct it

The sacraments and the Church as means of grace

Rome teaches seven sacraments: baptism, confirmation, Eucharist, penance (confession), anointing of the sick, holy orders and matrimony (CCC 1113). They are 'efficacious signs of grace' that work ex opere operato, literally 'by the work worked', meaning they confer grace by the rite properly performed, not by the minister's holiness (CCC 1127-1128, 1131). The Catechism says the sacraments are 'necessary for salvation' for believers (CCC 1129).

Grace in this system is something like a spiritual quality infused into the soul. Baptism removes original sin and infuses sanctifying grace. Mortal sin destroys it (CCC 1861). Penance restores it. The Eucharist nourishes it. The Church, as the dispenser of the sacraments, is the ordinary channel of salvation. Leonardo De Chirico describes the Catholic system as resting on two hinges: a nature-grace interdependence (nature is capable of being elevated by grace and cooperating with it) and a Christ-Church interconnection (the Church is seen as a continuation of the incarnation, acting with Christ as mediator of grace). Seeing that system helps you understand why individual doctrines hang together.

What does ex opere operato mean, and how does the Catechism describe the role of the sacraments in salvation?Show answer

Ex opere operato means 'by the work worked': the sacraments confer grace by the rite properly performed, not because of the minister's holiness. The Catechism calls the seven sacraments efficacious signs of grace and says they are necessary for salvation for believers. Grace is infused by baptism, destroyed by mortal sin, restored by penance and nourished by the Eucharist, so the Church as dispenser of sacraments is the ordinary channel of salvation.

grace by the rite performed
seven sacraments necessary for believers
grace infused, lost, restored
Church as channel of salvation

Describe Leonardo De Chirico's 'two hinges' of the Catholic system and why seeing them helps.Show answer

The first hinge is a nature-grace interdependence: nature can be elevated by grace and cooperate with it. The second is a Christ-Church interconnection: the Church is seen as a continuation of the incarnation, acting with Christ as mediator of grace. Seeing the whole system helps you understand why individual Catholic doctrines hang together rather than treating them as unrelated.

nature-grace interdependence
Christ-Church interconnection
Church as continuation of incarnation
explains why doctrines hang together

The Reformation and the five solas

When Martin Luther posted his Ninety-Five Theses on 31 October 1517, the trigger was the sale of indulgences. The deeper issues soon became clear and were later summarised in five Latin phrases. (You met this story in The Story of the Church, Lesson 5, and the doctrines behind it in Know Your Faith, Lessons 1 and 7.)

Sola Scriptura (Scripture alone): Scripture is the only infallible rule of faith; church tradition and councils are real but fallible authorities under it.
Sola gratia (grace alone): salvation is God's unearned gift, not a reward for cooperation.
Sola fide (faith alone): sinners are declared righteous by faith, apart from works.
Solus Christus (Christ alone): Christ is the only mediator and his single sacrifice is sufficient.
Soli Deo gloria (glory to God alone): all glory in salvation belongs to God.

What triggered the Reformation, and how would you summarise the five solas for a friend?Show answer

The trigger, when Luther posted his Ninety-Five Theses in 1517, was the sale of indulgences, but deeper issues soon emerged. The five solas say that Scripture alone is the only infallible rule, salvation is by grace alone as God's unearned gift, sinners are declared righteous by faith alone apart from works, Christ alone is the only mediator with a sufficient sacrifice, and all glory belongs to God alone. Tradition and councils are real authorities but fallible and under Scripture.

indulgences the trigger
Scripture the only infallible rule
grace and faith alone
Christ the only mediator; glory to God

Official teaching versus popular piety

Catholics vary enormously. Some never read the Catechism; some hold views Rome rejects; some are deeply devout but theologically untrained. When you meet a claim, ask: is this dogma (defined by a council or by an ex cathedra papal statement, one made 'from the chair' of Peter, which Lesson 2 explains), official teaching (the Catechism, encyclicals), theological opinion, or folk practice (a particular devotion, a local custom)? Do not hold a friend responsible for a superstition Rome itself does not teach, and do not let a friend say 'the Church doesn't really teach that' when the Catechism or Trent clearly does.

Gregg Allison's Roman Catholic Theology and Practice is useful here because it walks through the Catechism section by section, noting where evangelicals agree and disagree. Always cite paragraphs. It shows respect and keeps the conversation honest.

Why should you distinguish dogma, official teaching, theological opinion and folk practice when talking with a Catholic friend?Show answer

Catholics vary enormously, and not every claim or practice carries the same weight in Rome's own system. Distinguishing the levels keeps you from blaming a friend for a superstition Rome does not teach, and keeps a friend from saying 'the Church doesn't really teach that' when the Catechism or Trent clearly does. Citing paragraphs, as Gregg Allison's book does, shows respect and keeps the conversation honest.

Catholics vary widely
don't blame them for folk superstition
don't let real teaching be denied
cite paragraphs

Tone with Catholic family and friends

Chris Castaldo, a former Catholic, urges Protestants to listen first, ask good questions, and keep Jesus at the centre. Ask your friend, 'If you died tonight, what would you say to God about why he should accept you?' Many Catholics will answer with a mix of grace and their own effort, and that opens the real issue gently.

Avoid sneering at practices you do not understand. Avoid calling the Pope the antichrist in your first conversation, even if older Reformed confessions said so (WCF 25.6 in its original form; many Reformed churches have since revised or qualified it). Do not assume a Catholic is unsaved, and do not assume he is saved because he is religious. Talk about Christ's finished work, read Scripture together, and pray for your friend.

What tone does this section recommend with Catholic family and friends, and what question can open the real issue gently?Show answer

Listen first, ask good questions, keep Jesus at the centre, and avoid sneering at practices or calling the Pope the antichrist in a first conversation. Do not assume a Catholic is unsaved, nor assume he is saved because he is religious. A helpful question is, 'If you died tonight, what would you say to God about why he should accept you?', since many answers mix grace and effort and open the real issue.

listen and ask questions
no sneering or antichrist talk
don't assume either way
'If you died tonight...' question

In their own words

“Sacred Tradition and Sacred Scripture make up a single sacred deposit of the Word of God; both are to be accepted and honoured with equal sentiments of devotion and reverence.” (CCC 82, 97; Dei Verbum 9-10)

“The task of giving an authentic interpretation of the Word of God has been entrusted to the living teaching office of the Church alone, the Pope and the bishops in communion with him.” (CCC 85, 100)

“The sacraments of the New Covenant are necessary for salvation, and they act ex opere operato, by the very fact of the action being performed.” (CCC 1128-1129)

“Those baptised in other Christian communities are justified by faith in baptism, incorporated into Christ, and rightly called Christians, though their communion with the Catholic Church is imperfect.” (CCC 818, 838; Vatican II, Unitatis Redintegratio 3)

Key texts

Mark 7:6-13: Jesus judges the traditions of the elders by the written Word and rebukes 'making void the word of God by your tradition'. Tradition is not wrong in itself, but it must answer to Scripture.
2 Timothy 3:16-17: Scripture is God-breathed and makes the man of God 'complete, equipped for every good work'. This is the classic text for the sufficiency of Scripture.
Romans 3:21-28: Righteousness from God apart from the law, received through faith; we are 'justified by faith apart from works of the law' (3:28). The centre of the Reformation.
Acts 17:11: The Bereans tested even the apostle Paul's preaching by the Scriptures and are called noble for it. A model for testing every teacher.
Ephesians 4:15: 'Speaking the truth in love.' Both halves are required in conversations with Catholic family.

Objections and answers

Try answering each one yourself before you open the response.

“You Protestants say you agree with us on the Trinity and the Creeds. But you only got those from the Catholic Church. Why accept Nicaea and reject Trent?”Show a response

We accept Nicaea not because a council said it but because it faithfully summarises Scripture; the Nicene fathers themselves argued from the Bible against Arius. Councils have real but derivative authority. Article 21 of the Church of England's Articles and WCF 31 (31.4 in the original numbering, 31.3 in the American revision) say councils may err and must be tested by Scripture. That is why we can accept Nicaea and Chalcedon and reject Trent: one set of decrees agrees with Scripture, the other, on justification and the Mass, contradicts it. The question is not which councils we like but which ones Scripture confirms. The same test you would apply to a council like Ariminum (359), which drifted toward Arianism, we apply to all.

“Most Catholics I know don't believe half the things you're attacking. Isn't this just an argument with a caricature?”Show a response

Fair challenge, and it is why we distinguish official teaching from popular practice. I am not criticising what an individual Catholic happens to believe, but what the Catholic Church binds on its members: the Catechism, the Council of Trent, Vatican I and the Marian dogmas. Those are the Church's own documents and paragraph numbers. If many Catholics do not believe them, that is worth exploring, because the Church says these teachings are not optional. I would rather talk with you about what you actually believe and then look together at what Rome teaches and what Scripture says.

“Christianity was one Church until Luther split it. The Reformation caused thousands of denominations. Isn't division itself proof the Reformers were wrong?”Show a response

The church was already divided long before Luther: East and West split formally in 1054, and the papacy itself had rival claimants during the Western Schism (1378-1417). Unity in Scripture is unity in the truth of the gospel (Galatians 1:8-9), not mere institutional unity; Paul opposed Peter publicly when the gospel was at stake (Galatians 2:11-14). The large denomination counts often quoted are inflated by counting every independent congregation; Protestants who hold the historic creeds and the solas agree on far more than the number suggests. And Catholics themselves differ widely on many issues, from liberation theology to traditionalism.

“We agree on the Trinity, the deity of Christ and the Creeds. Aren't the rest just minor differences? Why can't we simply unite?”Show a response

I'm genuinely glad for what we share, and I mean it. We confess the same Trinity, the same Christ who is fully God and fully man, his virgin birth, cross, resurrection and return. A Catholic friend is not an unbeliever in the way an atheist is. But the remaining questions are not minor. They concern how Christ's saving work reaches a sinner and who has authority to say so. Is a sinner declared righteous by faith alone, or through sacraments and cooperation with infused grace? Is Scripture the only infallible rule, or one leg alongside Tradition and the Magisterium? The Reformers believed the gospel itself was at stake, and Paul says that adding a requirement to the gospel makes it 'a different gospel' (Galatians 1:6-9). Unity that ignores the gospel isn't real unity. Let's keep talking about Christ's finished work.

“Luther was only upset about the sale of indulgences. The Church stopped that long ago, so the Reformation should be over.”Show a response

You're right that indulgences were the trigger in 1517, and that they are no longer sold. But the deeper issues came out quickly, and they are summed up in the five solas: Scripture alone as the only infallible rule, grace alone, faith alone, Christ alone, and glory to God alone. Those questions were never about money. The Council of Trent later answered them by condemning justification by faith alone, and its decrees still stand as Catholic teaching. The Catechism also still teaches the doctrine of indulgences, as a remission of temporal punishment through the Church's treasury of merits. So the question remains: is Christ's one sacrifice enough for a sinner who trusts him, or must something be added? Romans 4:5 says God 'justifies the ungodly' who trust him. That is still worth talking about.

Written task

Write a 250-350 word letter to a Catholic relative (real or imagined) in which you (1) affirm genuinely the beliefs you share, (2) explain in your own words the Catholic understanding of Scripture, Tradition and Magisterium, citing at least two CCC paragraphs, and (3) gently state why you hold to sola Scriptura, inviting further conversation.

Hand this in to Mr Scott. He will look for:

Names specific shared doctrines warmly and sincerely, not as a set-up
Accurately represents the Catholic view with at least two correct CCC or Dei Verbum citations
Gives at least one biblical reason for sola Scriptura (e.g. 2 Tim 3:16-17, Mark 7)
Maintains a respectful, non-condescending tone that invites dialogue
Keeps Christ and the gospel at the centre rather than winning points