The Heart Undivided: How Believers Struggle with Doubt

Rev. A. Craig Troxel

Jude 22 - "have mercy on those who doubt"

This article is the second of a two part series. See part 1: "The Heart Divided: When Believers Struggle with Doubt".

The Heart of Faith

It was stated in the previous article that doubts come in various forms. This variation simply reflects the nature of faith, which is manifold as well. This came freshly to light in the Reformation. Faith is one of the biblical doctrines the Reformers re-discovered and significantly recast. Saving faith must include knowledge and assent. No one has ever questioned this. But the reformers also reasserted the biblical notion of trust. In the words of our confessional standards, faith is principally "accepting, receiving and resting" upon Christ alone for salvation (Conf. 14.2). As John Murray put it, faith must pass from cognition to conviction, and from conviction into confidence. Faith is a "hearty reliance." i It is a "movement of the whole inner man." ii In other words, faith is belief and trust. It has content and commitment. It affirms that God is true and trustworthy. We should not be surprised that faith has these various parts to it; because faith's manifold nature simply reflects its origin: "…if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved. For with the heart one believes and is justified, and with the mouth one confesses and is saved" (Rom 10.9-10). Doubt's diversity reflects our faith, just as faith reflects the various capacities and functions of our heart.

"Heart" is the Bible's most-used word to describe the governing center of our life. It is the inner person in both its integrity and its intricacy. Understood simply, the word "heart" reflects the unity of our inner being. Understood comprehensively, the word "heart" describes the complex interplay of our inner being—our mind, desires and will. The mind of the heart includes our intellect, understanding, imagination, and memory—what we know. The desires (or what the Puritans called the "affections") include our longings, cravings, feelings, "treasures"—what we love. The will of the heart includes our decision-making and volition (whether strong or weak)—what we choose. A biblical view of faith must adequately envelop these various functions of the heart. It is no wonder then that doubt reflects this same complexity. Simply put, doubt is the heart divided. Doubt is the mind trying to discern the endless and alluring voices of knowledge that appear to challenge the claims of God's truth. Doubt is the struggle we feel with the appearance of a new lover competing for our heart's first and true love, Christ. Doubt is our inability to resist the draw of an appealing choice that we sense will endanger our commitment to God. Appreciating that our doubts come at us from different angles and in different forms helps us to face them more accurately and with greater skill. iii A good diagnosis will lead to a more effective prognosis. But one thing ought to be clear, our doubts are always and ultimately about the heart.

Faith of the Heart

Doubt and the Heart's Mind

As we face intellectual or doctrinal doubts, we must appreciate that the heart's mind needs constant attention. It must be guarded against conformity to the world's ways of thinking and it must be continuously renewed (Rom 12.2). We must dedicate ourselves to the ongoing sharpening and deepening of our understanding of the faith. This means that we are not just reviewing what we believe, but also why we believe. This is one way in which we need to think about how we prepare our covenant youth for a godly life in the world. As important as it is, if we only catechize we are not doing enough. We must also explain and defend why we believe what we believe. When we teach them it must include answering questions like: Why is this doctrine important? Why does this matter? How has this doctrine been challenged historically and how is it being attacked today? We must constantly be about the work of equipping our church members of all ages so that at the first sound of the world's dissent they do not head off running from the battle field. We need to train them so that questions do not rattle them, because they are seasoned in listening carefully and accustomed to sparring graciously. Their "coaching" will have taught them to defend the truth with courage and to speak the truth in love. They have not simply heard rumors that many doctrines are floating in the wind. They know them by name and they know their weaknesses. They can answer them.

When we settle down to address doubts of the mind our first order of business is to make sure that our faith is teachable; that we are willing to listen to God and appreciate again the benefits of having a Christ-like attitude of humility (Php 2.5). We must be alert to the ways in which our doubts reveal a worldly vantage point of self-importance, greed, self-absorption, materialism or laziness. To love God with all our mind demands no less. To embrace the truth demands no less. And the benefits of God's truth, if given a chance, are remarkable. His truth gives us real answers, peace, comfort, joy, hope, and assurance. It can set us free. A heart filled with doubt is double-minded. The heart filled with truth is in its right mind. Herein lies the importance of the Word of God as a means of grace—whether read, preached, heard, or memorized and meditated upon. The renewal of the mind receives its grist from the truth, which God has given to us for our benefit—sometimes to teach, sometimes to rebuke, sometimes to correct, sometimes to train in righteousness. Nothing is as useful in our struggles with intellectual doubt like God's words. It is up to the task.

Doubt and the Heart's Desires

Many of our doubts are not about what we think but about what we feel, want or love. These desires are vying for first place in our heart. This happens when we see others prosper and our envious heart reconsiders its loose grip on the things of this world. This happens when someone catches our eye and we wonder, like Eve, why God wouldn't want us to take just one taste and be happy. This happens when tragedy comes and we ask, "How could God let this happen to me?" It was not C.S. Lewis' atheist colleagues who sent his faith into a tailspin. It was the death of his wife. Similarly, our views on sexual ethics and marriage are challenged more often by our own desires or the life style of a close friend than philosophical viewpoints. These are the things that pressure us to change our views about God and his trustworthiness. They tempt us to serve two masters. Christ warns us that this is impossible. You will eventually love the one and hate the other (Mt 6.24). The irony is that these same difficult seasons of sufferings are the very means by which God refines our faith so that we will love him with all our heart. Just as gold is purified and made more valuable by fire, our faith is similarly purified by the heat of suffering in order to make us stronger. By making us pass through the fiery trials God is able to scrape off the dross of lesser motives and attitudes in order to make our faith more steadfast. Illness, loneliness, pain, failures, weakness and delayed answers to prayer become the very means by which God pushes us towards undivided loyalty. He peels back the layers of self-sufficiency, thaws our frigid souls, and shatters thick walls of pretense in order to trust him more and more. God's way to address our desires of doubt is to assault them outright and bring to bear something better. Herein lies the importance of the sacraments as a means of grace. For example, the Lord's Supper calls us back to the very core of the Gospel. As the supper places the symbols of Christ's incomparable love in our hands, the Spirit pours the inestimable power of that love into our hearts. The supper is all about purifying our hearts by opening our eyes to the fading beauty of worldly loves and fortifying our affections in the everlasting beauty of God's love in Christ. The battle in our heart is over what we will love most. The supper helps us by reminding us of the one who loves us best.

Doubt and the Heart's Will

Doubts also involve the heart's will. When we are unsure of ourselves we are unable to act. We are often immobilized by our fear of failure or by what others may think. We are unable to resist certain kinds of temptation and that weakness makes us question our dedication as followers of Christ. We lose many of these battles before they ever began because we have lost our confidence. These are helpful indicators that the faith of our heart lacks proper resolve. What can we do? A good beginning point is to remind ourselves that it is not faith that saves. It is faith in Christ that saves. The nature of saving faith is that it does not look to itself, but outside of itself. As John Murray put it, faith is not introspective. It is extraspective. Psalm 112 makes this very point. It states that the righteous man "will never be moved" and that because his "heart is steady" he "is not afraid of bad news." How is this possible? It is because "his heart is firm, trusting in the Lord." He is leaning on the rock of his salvation. Christ makes the same point by analogy. The person whose faith is built upon Christ and his teaching is like the house that is able to withstand the rising flood and stormy wind. Even the weakest faith can be a saving faith provided it is looking to Christ as the author and finisher of faith. It will get the victory in the end, because it is in Christ. So we must constantly look to God to fortify our faith.

Herein lies the importance of prayer. Calvin taught that prayer was the chief exercise of faith. It has to be. It is cut from the same cloth. Prayer gives voice to faith's inability to sustain itself. It ever looks to the strength of the Lord for its sustenance. This is why Paul reminds us to be strong in the Lord and in the strength of his might. This is why David sought the Lord to sustain him with a willing spirit (after caving into such egregious sin). This is why even the weakest flickering flame of faith can still get the victory in the end, because it is sustained by him who will not snuff out a smoldering wick. God will sustain what he began in us. He is able to do abundantly more than anything we can imagine. Those formerly weak become warriors. Those formerly known as compromisers (like Thomas Cranmer) die as martyrs. Those who humble themselves before God in prayer will be exalted by God and his grace.


Until we see the Lord Jesus Christ face to face our faith will be challenged by doubts of every sort: those that will test the heart's mind and the foundations of what we know; those that will strain the heart's desires and our loyalty to what we love; and those that will tempt the heart's will and the strength of our resolve. Folly smirks and says to ignore them. Fear shrinks back and says to run away. Faith says to take them seriously. As we step forward to confront these challenges we do so clinging to the promises of God's Word—every one of which finds its "yes" and its "Amen" in Jesus Christ. Again and again we will find success by trusting in Christ; believing in him, accepting his rule, resting in his word, and yielding to his ways. It is by looking to Christ with all our heart that the raging doubts will subside like the sea when it heard his voice. It always comes back to our personal walk with him and learning that he is not just true; he is trustworthy. Let us continuously draw near to Christ with a true heart, and as he graciously allows, discover the full assurance of our faith; the assurance that "does not lie in us, but in him." iv

i Louise Berkhof, Systematic Theology, 4th ed. (Grand Rapids: Eerdmans, 1984), 503.

ii B.B. Warfield, "Biblical Doctrine of Faith," Works (1929; reprint, Grand Rapids: Baker, 1991) 2.501-502

iii The author again acknowledges his significant dependence upon Os Guinness' Doubt: Faith in Two Minds (Herts, England: InterVarsity Press, 1976), which provided or inspired every good idea found in this article and the one that preceded it.

iv Sinclair Ferguson, The Whole Christ (Wheaton, IL: Crossway, 2015), 213.


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