What Is Necessary for a Christian to Believe?

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The questions often arise: “What must a Christian believe to be saved”? or “What are the essentials?” Most often the broad evangelical answer is “not much.” The tendency is toward minimalism in doctrine (belief) and practice. In some circles it is enough to say that one came forward at a rally, prayed a prayer, and signed a card (or clicked yes on a website). The Reformed Churches, however, confess a different answer to that question in the Heidelberg Catechism:

Q. 22. What then is necessary for a Christian to believe?

A. All that is promised us in the Gospel, which the articles of our catholic, undoubted Christian faith teach us in sum.

The catechism begins with the gospel, the good news about Jesus the Messiah, which is shorthand for his incarnation, death, resurrection, and ascension for us sinners—but there is more.

The Apostles’ Creed contains the articles of our catholic, undoubted faith.

The gospel as we understand it is summarized not just in those events but in “the articles of our catholic, undoubted Christian faith” that teach us what is necessary for us to believe. The articles to which this answer refers are the twelve articles of the Apostles’ Creed, which are in three sections, organized by the Holy Trinity:


  • I believe in God the Father, almighty, maker of heaven and earth,


  • And in Jesus Christ, his only begotten Son, our Lord,

  • Who was conceived by the Holy Spirit, Born of the virgin Mary,

  • Suffered under Pontius Pilate, crucified, dead and buried; He descended into hell;

  • The third day He rose from the dead;

  • He ascended into heaven, and sits at the right hand of God the Father almighty;

  • Thence He shall come to judge the living and the dead.

Holy Spirit

  • I believe in the Holy Spirit,

  • The Holy Catholic Church, The communion of saints,

  • The forgiveness of sins,

  • The resurrection of the body,

  • And the life everlasting.

According to the Reformed understanding, all twelve articles are under the heading “gospel.” This doesn’t mean that there isn’t a narrow sense of the gospel (as sketched above), but it does mean that, when we answer the question of what must be believed, we do not stop at the narrow sense of gospel. We include in it the doctrine of the Trinity, a doctrine of God, a doctrine of creation and providence, of sin, of Christ, of salvation, of the church, sacraments, and last things.

Our doctrine of God is intimately connected to our understanding of man, salvation, church, and worship.

Modern evangelical answers to this question have focused on Christ to the exclusion of these other doctrines, but in Reformed theology they’re all connected. Our doctrine of God is intimately connected to our understanding of man, salvation, church, and worship. The Reformed faith, however, is biblical and catholic, i.e., we believe what the Scriptures teach about God, man, Christ, salvation, etc., as understood by the church in all times and places.

In contrast, for evangelicals, so long as one affirms a personal relationship with the risen Christ, everything else is negotiable. It is not even always certain what an evangelical means by “Christ.” Is she referring to the Christ of Scripture and history, confessed in the Creed, or to the Christ of subjective, mystical experience?

The Reformed answer to the question, “what must a Christian believe?” is not minimalist, but neither is it maximalist. We don’t ask Christians to believe everything possible. We ask them to believe all that is necessary. There are limits to what may be set as a condition of salvation. There is a hierarchy of beliefs. They aren’t all equally ultimate or necessary. There are fundamentalist groups that require adherents to believe that the King James Version of the English Bible is the only acceptable translation, but that’s not a necessary belief. The King James Version is a wonderful piece of work, but it’s just one translation among many.

The Geneva Bible pre-existed the KJV, the Tyndale translation pre-existed the Geneva Bible, and we’ve had many fine translations since 1611. Others would set the length of creation days as a necessary belief. One is certainly entitled to one’s opinion about the meaning of the “day” in Genesis 1 and 2, but historically the emphasis has been on the reality of the creation days and upon the truth that we are created and not the Creator.

The Christian faith is distinct from other religions.

Reformed churches are Trinitarian. This puts us at odds not only with Jews and Muslims who reject the Trinity, but also with those evangelicals who seek some détente with Mormonism, which denies the catholic (universal) Christian doctrine of the Trinity.

We believe in divine providence, that God is the same God who spoke creation into existence by the power of his Word and is actively upholding and governing all things. We reject deism. We reject pantheism (everything is God). We reject panentheism (everything is in God). God is. He isn’t becoming. Whatever comes to pass does so only because and under the control of God’s good providence.

We believe the catholic doctrine of the two natures of Christ as summarized in the Nicene-Constantinopolitan Creed (381), in the Definition of Chalcedon (451), and the Athanasian Creed (7th century). He is true God and true man. He remains one person with two distinct, united, inseparable, unconfused natures. What is true of Christ’s natures is true of his person, but the distinct properties of each nature are unchanged.

We are not Gnostics. We believe that God created humanity good, righteous, and holy; able to fulfill his law and enter into eternal blessedness through obedience to that law (the commandment of life—the covenant of works). Our first parents, Adam and Eve, disobeyed God, and Adam, as the legal representative of all humanity, died spiritually. In Adam’s fall into sin, death, and guilt, all humans were implicated. We are all born in sin and death.

The Spirit gives the grace of faith to all Christians.

There is salvation by (a covenant of) grace alone, through faith alone, in Christ alone. Just as God, in the garden, offered to Adam life on condition of obedience, so now he has promised life to his elect on the basis of the obedience of the Second and Last Adam, Jesus. His Spirit grants life to those for whom he obeyed, suffered, was crucified, died, was buried, and was raised, and for whom he now intercedes.

The Spirit gives the grace of faith to those to whom he has given life, and through faith he grants us free acceptance with God, unites believers to the risen Christ, and adopts them as sons. We do believe heartily in a personal communion with the risen Christ, but the Christ to whom we are united, with whom we commune, is the Christ of Scripture and history. He is not the figment of our imagination or the creature of our experience.

The true church exists where the gospel is preached purely, the sacraments (baptism and the Lord’s Supper) are administered purely, and where there is discipline.

We are not saved alone, nor are we saved to be alone. The Triune God administers his salvation in the visible church. Where the gospel is preached purely, the sacraments (baptism and the Lord’s Supper) are administered purely, and where there is discipline, there is a true church. In those assemblies is where the Spirit is at work bringing the elect to faith and where believers are growing in sanctity as a consequence of God’s grace and fellowship with one another.

These visible covenant assemblies are mixed. In them are believers, those who are yet to believe, as well as those who profess faith but who do not believe. There has always been a universal church—composed in all times and places of believers—since the beginning of the world, and there shall always be this body, united by true faith, in the visible assembly.

Believers are freely accepted by God (justified) through faith (knowledge, assent, and trust) alone in Christ.

In the visible church is where all believers are ordinarily found. Believers are those who have been given a knowledge of the faith, assent to the truth of the faith, and a hearty trust that the promises of the gospel are true not only for others but for themselves also. Believers are freely accepted by God (justified) through faith (knowledge, assent, and trust) alone in Christ.

In that communion of saints God uses visible signs of his promises. To those who believe, these signs (sacraments) testify that what they signify is really true for the believer. Christians follow in the footsteps of Abraham and Moses by initiating their children into the visible covenant community in baptism and, upon profession of faith, communing with him at the Lord’s Table. These signs and seals are not magic; but they do tell the truth, and the Spirit does use them to strengthen our faith and to help us grow in Christlikeness.

Sin (violation of God’s holy law) corrupted creation and especially human nature and brought death, but that is not the end of the story. Just as there is forgiveness of sins in Christ, so too our Lord has, by his bodily resurrection, begun to reverse the effects of the fall. His bodily resurrection is a promise that, when Christ returns, believers too will be raised from the dead. As we wait for the final day, we do so with the confidence that Jesus ascended bodily and that he, in his true humanity, is at the right hand of our Father praying for us.

We live our life in union with Christ and in communion with believers.

The new life that believers have by grace alone is a down payment of the eternal life that is to come in the new heavens and new earth. We live our life in union with Christ and in communion with believers, patiently waiting and serving him by fulfilling our earthly vocations as citizens of his twofold kingdom (eternal and temporal).

The Christian faith has objective content that must be believed. Those propositions are more extensive than many might like to think, but all that content must be appropriated personally by faith or it remains only theoretical. The Spirit works through the proclamation of this gospel, these truths, to produce new life, true faith, and sanctity. Those to whom he has given new life he has also given a new identity shaped by the catholic, Christian faith.

The biblical faith, the catholic faith, is an integral, coherent, whole. It isn’t a patchwork, but neither is it an endless garment.

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