Gospel Guidebook: Getting and Keeping It Right 
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Problems with the Heidelberg Catechism's Description of Faith
by Robert P. TerryUpdated May 8, 2026
The Heidelberg Catechism is an important exposition of doctrine for Reformed believers. The catechism consists of 129 questions and answers that can be divided in four basic units: man's misery, man's redemption, thankfulness, and prayer. The catechism was mainly composed by Zacharius Ursinus (1534–1583) and was published in 1563. The original document was written in German, but there are at least two English versions. In this article, I will be criticizing the catechism's description of faith based on the English version found here, but everything I say in regard to that version equally applies to the English version found in Philip Schaff's "Creeds of Christendom Volume III" available here. I am unable to read German, but I did translate the German version found in Schaff's work using Deepl to confirm roughly that the English version I used for this critique adequately reflected the German.
In this article, I will be focusing on the Heidelberg Catechism's description of faith given in Lord's Day 7, but the problems created by wrongly understanding the nature of faith are pervasive throughout the whole catechism. For example, the catechism says in Lord's Day 32 that we "may be assured of our faith by its fruits." This is a serious error that has caused endless amounts of grief for people with tender consciences, keeping them trapped in a system of works salvation. For people who are interested in why this is an error, I recommend reading the following six articles in order, 1, 2, 3, 4, 5, and 6. It will take a considerable amount of time to read these articles, but if you make an effort to understand the arguments, I am sure you will be highly rewarded and set free from false idea that we can get assurance of faith by looking at our works.
Moving on, the Heidelberg Catechism says in Lord's Day 7 (omitting the Scripture cross references available here):
Q20 Are all men, then, saved by Christ just as they perished through Adam?
A20 No. Only those are saved who by a true faith are grafted into Christ and accept all his benefits.
Q21 What is true faith?
A21 True faith is a sure knowledge whereby I accept as true all that God has revealed to us in his Word. At the same time it is a firm confidence that not only to others, but also to me, God has granted forgiveness of sins, everlasting righteousness, and salvation, out of mere grace, only for the sake of Christ's merits. This faith the Holy Spirit works in my heart by the gospel.
As I explained in article 6 above, as well as in Q&A #6 available here, we should be wary any time the word faith is modified by adjectives like "true," "hearty," "upright," etc. Those modifiers indicate, among other things, that a sleight of hand is at play, in which the word faith will be hijacked and transformed into an appropriating act that requires, at the very least, some sort of "heart work." And this is exactly how the catechism describes so-called "true faith" in A20. However, the word faith (Gr. pistis, which could also be translated as "belief," since it is the cognate noun of the verb "believe") as used in the Bible and in every other realm of life is not an appropriating instrument, and the only thing faith can accept are propositions that it regards as being true (see my article here where I answer an objection to this statement). The benefits of the Gospel are not aspects or elements of faith, nor can faith appropriate them. Rather, the benefits of the Gospel are things that are simply true of people who believe the Gospel. And because they are true of people who believe the Gospel, people who believe the Gospel come to enjoy them. For example, when we say that assurance is of the essence of faith (based on Hebrews 11:1), what we mean is that we are assured that the content of some proposition is true. In the case of the Gospel, we are assured that the content of the Gospel is true. However, it would be a mistake to think that by assurance we mean the benefits of the Gospel. The benefits of the Gospel are enjoyed after believing the Gospel. (If you are unsure about the content of the Gospel and the nature of faith, please see my articles Jesus Is the Christ, the Son of God, What is the Gospel and the Nature of Faith?, and Q&A on Faith). Having said this, we must move on because my real intention in this article is to examine A21.
Getting into A21, I'd like to skip the first sentence for the time being. As mentioned above, I disagree with the concept of "true faith" and the nuance and implications of the cross reference to James 2:19 (see my article here for a discussion on James 2:14-26), but I'd like to focus on the second sentence where it says that faith consists in a "firm confidence that not only to others, but also to me..." This sentence is problematic because Christ did not die for each and every sinner that ever lived without exception, and thus the proposition "Christ died for me" cannot be part of the Gospel or made to be a qualification for believing the Gospel. However, even if we want to dispute this point and say that Christ did die for "the sin of the whole human race" (see A37), a "firm confidence that not only to others, but also to me..." would still require appropriating what isn't applicably and efficaciously true until it made to be true through some elusive and mystical "true faith" worked in the heart (which is ascribed, of course, to the Holy Spirit to obfuscate the underlying scheme of works salvation). However, for justification to be wholly apart from works, what Christ did for sinners cannot be mixed with what the Holy Spirit supposedly does in sinners. Appropriating the proposition "Christ died for me" through "heart work" would fall within the realm of what the Holy Spirit does in sinners. If this is true, justification would no longer be wholly apart from works, but would involve a transformative element in the heart, and the cross of Christ would no longer be the all-sufficient work of justification, but would become merely the ground of justification. The Heidelberg Catechism basically teaches that those who are saved are those who confirm their status as one of the elect through some elusive heart work, which in order to obfuscate the implications of working for one's salvation, it attributes to the Holy Spirit. (See my articles "Christ Died for Me" is NOT the Gospel for a more detailed explanation.)
Now, looking at A21 as a whole, what I see is this: (1) "sure knowledge," (2) "accept as true all," and (3) "firm confidence." Ignoring the problems created by the qualifiers "sure," "all," and "firm," the catechism describes faith in terms of the three components commonly referred to by theologians as notitia (the content of something to be believed), assensus (the conviction or persuasion that the content is true), and fiducia (which as a bare minimum includes an appropriating personal trust and reliance, but can include other things such as "surrender of the soul," as described by Reformed theologian Louis Berkhof on page 505 of his Systematic Theology). In contrast to this "true faith," the word faith as used in the Bible and in every other realm of life outside religion simply means to be persuaded by the evidence for a thing, requiring only notitia and assensus. Please understand this: if we really believe that "Christ did it all" (John 19:30, etc.), then faith can require no more than notitia and assensus. The introduction of fiducia as an element of faith requires work on the part of the sinner that nullifies Christ's work.
Let's consider this excerpt from the Routledge Encyclopedia of Philosophy on the topic of Belief:
We believe that there is coffee over there; we believe the special theory of relativity; we believe the surgeon; some of us believe in God. But plausibly what is fundamental is believing that something is the case – believing a proposition, as it is usually put. To believe a theory is to believe the propositions that make up the theory, to believe a person is to believe some proposition advanced by them; and to believe in God is to believe the proposition that God exists. Thus belief is said to be a propositional attitude or intentional state: to believe is to take the attitude of belief to some proposition. It is about what its propositional object is about (God, the operation, or whatever). We can think of the propositional object of a belief as the way the belief represents things as being – its content, as it is often called.
This explanation and the conclusion in the last two sentences describe the nature of faith (Gr. pistis = belief). This description applies to every realm of life, including religion, from the secular standpoint of the encyclopedia's contributors. However, it is only in the realm of religion that theologians smuggle this fiducia and other baggage into the meaning of faith, thereby hijacking faith, holding it hostage, and transforming it into something that bears the name faith but is actually something very different. But as I have described in several articles on this website (see those linked above, but especially here and here), we have the biblical testimony that what faith means in every other realm of life is exactly what it means when applied to the Gospel (see, for example, Jesus' description of "believing" in John 3:11-12, John the Baptist's in John 3:32-36, the Apostle John's in 1 John 5:9-10, and the author of the Hebrews' description of faith in Hebrews 11:1. See also my commentary on James 2:14-26 here).
The Heidelberg Catechism's description of faith is counterfeit, unbiblical, and dangerous. As described in the encyclopedia above, faith represents its object. In terms of justification by faith, the object of faith must be the Gospel. But since the catechism misunderstands the nature of faith, it also misunderstands the Gospel. It is because of documents like the Heidelberg Catechism that millions of Reformed believers live their lives either deluded, thinking that they appropriated justification to themselves by "Holy Spirit-produced" fiducia, or they live with great anxiety because they doubt the quality of their fiducia. Little do they know that they are practicing a form of mysticism and works salvation under the guise of so-called "true faith." In contrast to the mystical "heart work" of fiducia, whereby the sinner must appropriate to himself things that aren't true until they are believed, when God through His Holy Spirit wants to open the eyes of one of His elect to see the things that are true regardless of whether or not they are believed, He shines upon him the content of the Gospel to give him knowledge of the glory of God in the face of Jesus Christ (Acts 26:18, 2 Corinthians 4:3-6).