Christian discipleship is inseparable from change. Jesus did not merely call people to new beliefs or outward conformity, but to lives that are genuinely transformed. Yet transformation remains one of the most misunderstood aims of Christian ministry. Churches teach faithfully and encourage obedience, yet often find that deep patterns of sin persist beneath improved behaviour.

At the Heart Matters Conference 2025, Andrew Katay addressed this tension by returning to a question Scripture itself presses relentlessly: what is the human heart, and what role does it play in spiritual change? He explained that lasting transformation is impossible unless the heart is properly understood and intentionally addressed.

In the Great Commission, Jesus commands his followers not only to baptise, but to teach obedience. Discipleship, therefore, cannot be reduced to managing behaviour. It is about forming people whose lives are genuinely reshaped. If the church is to participate in God’s work of renewing human beings, it must be clear about how human beings actually change.

Scripture and the centrality of the heart
Scripture speaks of the heart with striking seriousness. Far from being a poetic synonym for emotion, the heart is presented as the centre of human life. Proverbs describes it as the source from which the whole course of life flows: “Keep your heart with all vigilance, for from it flow the springs of life” (Proverbs 4:23). Actions and habits do not arise independently. They flow from something deeper.

This emphasis appears throughout the biblical narrative. In Exodus, Pharaoh’s resistance is traced to a hardened heart before it appears in hardened decisions. In the Psalms, trust, gladness, fear, and thanksgiving are repeatedly located in the heart. Jesus reinforces the same truth when he confronts religious moralism, insisting that defilement proceeds from within rather than from external observance (Mark 7:20–23).

Paul’s analysis in Romans 1 presses further still. Sin is not described merely as moral failure, but as idolatry driven by “the lusts of their hearts” (Romans 1:24). Behaviour is the outcome. The heart is the engine.

Five dimensions of human experience
Human experience can be described across five interconnected dimensions: mind, will, body, guts, and heart. The mind thinks. The will chooses. The body acts. The guts are where emotions are experienced viscerally, often located in the inward parts rather than the heart itself. The heart, however, operates at a deeper level. It is the seat of love, desire, worship, trust, and rest. It is what we treasure, what we fear losing, and what we believe will give us life.

This distinction explains why genuine change cannot be produced by information alone or by discipline alone. Scripture recognises that it is possible to know the truth without loving it, to obey externally while remaining inwardly distant, and to experience strong emotion without spiritual renewal. The heart is connected to every other aspect of human life, yet it is not reducible to any of them.

Katay summarised the dynamic in this way: what the heart desires, the will chooses, the mind justifies, the body acts, and the guts feel good or bad about it. The movements we can see and manage most easily are not the ones doing the decisive work. When ministry focuses primarily on behaviour, decision-making, or even emotional experience, it can produce visible change while leaving the heart itself untouched.

The heart as the organ of love
If the heart is the centre of human experience, then its primary activity is love. Scripture consistently portrays the heart as what desires, treasures, worships, fears, rejoices, and grieves. These are not merely emotional reactions, but expressions of what the heart judges to be good and worthy.

This clarifies why sin is never merely about rule-breaking. Drawing on Augustine, Katay described sin as disordered love. Human beings are created to love many things. Scripture does not deny this. We are meant to love God, neighbour, family, and creation. The problem is not that we love, but that we love out of order.

Romans 1 illustrates this. Humanity does not lose the capacity to love, but redirects it. When God is exchanged for created things, desire intensifies and distorts. The heart fastens onto something else and demands from it what only God can give.

Why surface-level change is misleading
One of the most pastorally significant implications of this framework is its explanation of incomplete change. People can change their behaviour dramatically without becoming more godly. They can exchange one sinful pattern for another that appears more respectable.

Katay warned against mistaking such sideways movement for spiritual growth. A person may abandon a destructive habit not because they love God more, but because they now love approval, control, or reputation more than they love the first sin. From the outside, this looks like progress. At the level of the heart, nothing has been reordered.

This is why moralism ultimately fails. When obedience is produced through pressure or external accountability alone, behaviour may improve, but love remains untouched. The same is true of intellectualism. Accurate theology, when detached from affection for God, can inflate pride rather than deepen devotion.

In both cases, the heart is bypassed. And when the heart is bypassed, lasting transformation does not occur.

How real change happens
If sin is rooted in disordered love, repentance cannot stop at behaviour or willpower. Simply resolving to “try harder” addresses only the surface.
Scripture presents a different path. Change happens when something new becomes glorious to the heart. Sinful desires are not removed by force, but displaced by stronger affection. The heart cannot be emptied. It must be reoriented.

This is why the gospel must be more than instruction or exhortation. It must present Christ himself as worthy of love, trust, and delight. As the beauty and sufficiency of Christ become vivid, the heart begins to loosen its grip on lesser things. Obedience then follows, as the fruit of new affection.

Katay noted that sin occurs not because Christians stop loving God, but because God becomes less vivid to the heart in a particular moment than the thing being pursued. The issue is not the absence of love for God, but the relative weight of competing loves.

Godliness as rightly ordered love
From this perspective, godliness can be described positively. Godliness is not the suppression of desire, but the right ordering of desire. It is loving small things a small amount, medium things a medium amount, and great things a great amount, by loving God most of all.

This vision allows for joy without guilt and discipline without despair. Created pleasures are not enemies, but gifts. The danger lies in asking them to bear the weight of ultimate meaning.

The implications are far-reaching. Repentance that stops at confession and renewed effort often fails because it never addresses what the heart was seeking. Ministry that aims primarily at compliance or information will always fall short. The calling of the church is to present Christ as supremely glorious, again and again, until hearts are genuinely reordered.