Catholic or Protestant? Does it matter?
the bible teaches that there is one true church.
by Robert McCurley
Are you a Roman Catholic? Perhaps you faithfully attend Mass each week, or maybe you’re a baptized Catholic who only steps into church on special occasions. You might have friends who are evangelical Protestants and passionate about sharing their faith. Have you ever wondered, “What’s the big deal?”
In a world plagued by pain and rising corruption, shouldn’t Catholics and Protestants see themselves as allies, united in tackling society’s problems? After all, isn’t the divide between them just a relic of history? Can’t the passage of time help us move past old differences to work together for a common cause? Yet the question lingers: What is the big deal? Do the issues that sparked the 16th-century Reformation still matter today? And what, exactly, are those issues?
The word “catholic” means universal, pointing to the one true church of Jesus Christ. The New Testament church “continued steadfastly in the apostles’ doctrine” (Acts 2:42), showing that we define the true universal church by its beliefs. We identify the true church of Jesus Christ by its faithfulness to biblical truth. Here are five key doctrines rooted in Scripture that mark the true church and reveal critical differences between evangelical Protestantism and Roman Catholicism.
the true church believes
in the doctrine of scripture alone
God speaks to us primarily through the Bible, his inspired and sufficient word (2 Tim. 3:16–17). We must not accept teachings that contradict Scripture, even if they come from an angel (Gal. 1:6–10). The true church bases its beliefs solely on the authority of the Bible, not on human traditions or church decrees (2 Cor. 11:1–4).
the true church believes
in the doctrine of christ alone
Jesus Christ is the only head of his church (Col. 1:18), possessing unrivaled authority to guide and rule it (Col. 2:18–19). Neither Mary nor the saints share his role as Lord and mediator (1 Tim. 2:5). The Holy Spirit, not the pope, serves as the sole vicar of Christ on earth, magnifying the Son of God and directing his church (John 16:5–15).
the true church believes
in the doctrine of grace alone
By nature, mankind is enslaved to sin, incapable of any spiritual good, and deserving of God’s wrath and curse (Rom. 3:10–23). Escape from this deserved judgment comes only through God’s free gift of grace in Jesus Christ (Rom. 6:23). Salvation does not derive from us bringing something to God—but from God giving something to us. Christ’s once-for-all sacrifice for sin is never repeated, whether in the Mass or elsewhere (Heb. 10:11–18).
the true church believes
in the doctrine of faith alone
Our sinful hearts pollute all attempts at good deeds, even our best efforts (Isa. 64:6). We cannot obtain salvation from sin by earning it through penance, the sacraments, purgatory, or any other works (Eph. 2:8–9). God provides the remedy for sin. We receive full and free forgiveness by believing in Christ—not faith plus good works (John 3:16). No other priest than Christ can grant this forgiveness of sin (Acts 10:43; John 14:6).
the true church believes
in the doctrine of the glory of god alone
Since salvation is entirely God’s gift, all glory belongs to him, not us (Rev. 5:11–14). Human pride and credit have no place (John 1:12–13). True religion humbles man and exalts God alone (1 Cor. 1:26–31). All good comes from him, and all glory goes to him.
The Roman Catholic Church denies these biblical truths, adding human traditions and merit to God’s perfect plan. Our present church connection matters. At stake is nothing less than our eternal destiny. We must face the most critical question in the world: How are we saved from our sins? Christ’s true church answers with the gospel. God accomplished for sinners what they could never do for themselves, providing a perfect salvation through his Son. Christ bore the sins of his people on the cross, satisfying God’s wrath and paying for the guilt of sin on the cross. In exchange, God credits Christ’s righteousness to their account, received by faith alone. Thereby, God remains both just and the justifier of all who believe (Rom. 3:26). We receive salvation from sin by trusting in Christ alone, resting in his finished work.
Rome’s denial of these vital truths constitutes the reason why evangelical Protestants broke from the Roman Catholic Church during the Reformation and remain separate today. These truths are not mere historical niceties—they concern the eternal state of our immortal souls. Leaving a cherished church is painful, but what could be costlier than eternity apart from God? Concern for ourselves and our family and friends compel us to turn our gaze from all else and to rivet our focus on Jesus Christ. Love for Christ calls us to love his word, his gospel, and his true church. That leads us to affirm that the differences between biblical Christianity and its alternatives are, indeed, a very big deal. ❦
The Rev. Robert McCurley is the pastor of Greenville Presbyterian Church in Greenville, South Carolina.