who called the Protestant doctrine of assurance “the greatest of all heresies.” What, after all, could be more offensive to a works-based and priest-imparted system of salvation than the possibility that assurance could be attained without either? If Christians can attain an assurance of eternal life apart from participation in the church’s rituals, what possible outcome could there be other than rampant antinomianism (the belief that God’s commandments are optional)?

But what exactly did the Westminster divines mean when they implied that our assurance is “founded upon” inward evidence? Behind this statement lies a practical syllogism:

(major premise) True believers demonstrate the fruit of the Spirit.
(minor premise) The fruit of the Spirit is present in me.
(conclusion) I am a true believer.

It should be obvious that the subjectivity of this argument is fraught with difficulty. While the certainty of salvation is grounded upon the (objective) work of Christ, the certainty of assurance is grounded upon the (objective) promises God gives us and the (subjective) discovery of those promises at work in us. And it is this latter consideration that gives rise to one or two problems.

Theologians have made a distinction between the direct and reflexive acts of faith. It is one thing to believe that Christ can save me (direct act of faith). It is another thing to believe that I have believed (reflexive act of faith). Apart from the first consideration (that Christ is both willing and able to save) there can be no assurance of faith. Indeed, it is pointless to move forward with the discussion about assurance apart from a conviction of the truthfulness of this statement: “Christ is able to save those who believe.”

Assuming, then, that there is no doubt as to the ability and willingness of Christ to save those who believe, how may I be assured that I have this belief? The answer of the New Testament at this point is clear: there is an “obedience of faith” (Rom. 1:5; 16:26). True faith manifests itself in outward, tangible ways. In other words, the New Testament draws a connection between faithfulness and the enjoyment of assurance. True believers demonstrate the fruit of the Spirit, and this fruit is observable and measurable.

Four Ways of Knowing

The Apostle John addresses this very issue in his first epistle: “I write these things to you who believe in the name of the Son of God that you may know that you have eternal life” (1 John 5:13). Apart from belief “in the name of the Son of God,” there is no point in furthering the discussion about assurance. The question at hand is, “How can I know if my belief is genuine?” And John’s answer emphasizes four moral characteristics of the Christian life.

First, there is obedience to the commandments of God. “By this we know that we love the children of God, when we love God and obey his commandments. For this is the love of God, that we keep his commandments” (1 John 5:2–3). True faith is not and can never be antinomian.

Second, there is practicing righteousness: “You may be sure that everyone who practices righteousness has been born of him” (1 John 2:29). Those who have a genuine faith will display a life of faith, a life molded and shaped by the obedience of faith. They demonstrate a desire for godliness.

Third, there is a radical breach with one’s former life. John expresses it radically (by employing a relative contrast in absolute terms): “We know that everyone who has been born of God does not keep on sinning” (1 John 5:18; cf. 3:6, 9). The explanation of this admittedly difficult language requires more space than is allotted here, but it is clear enough that a true and genuine faith is incompatible with a continuation in the pattern of sinful behavior that characterizes the life lived in unbelief.

Fourth, there is walking in love: “We know that we have passed out of death into life, because we love the brothers. Whoever does not love abides in death … whoever loves has been born of God and knows God” (1 John 3:14; 4:7). Loving our brothers and sisters is something dear to the Apostle John’s heart. After all, according to tradition, the elderly Apostle in Ephesus, carried by the arms of his disciples, was heard to repeat, “Little children, love one another.” And when asked why he kept repeating it, he answered: “It is the Lord’s command. And if this be done, it is enough.”

These four marks then collectively contribute to an assurance that our faith in Christ is genuine. But what if I cannot discern these outward evidences in myself and wonder if they are lacking? Should I then conclude that my faith is hypocritical or insincere? Yes, that is a possible conclusion. But it is not necessarily the correct conclusion, because our assessment of the evidence of outward faith in these four marks may be faulty. We may be too hard on ourselves. We may doubt what others can clearly see. Satan may cloud our thinking. The lack of consistency may lead us to conclude that no evidence at all is present. And personality and disposition may lead us to negative assessments when a more objective scrutiny deduces a different conclusion. But the possibility exists that our faith may be insincere. What then?

Faith in Evidence or Faith in Christ?

And it is here that differences of counsel appear. A predictable counsel might be, “Try harder.” It is a comment I most remember from annual school reports—“Could do better.” A person who doubts the genuineness of his faith due to inconsistency of behavior would then be urged to “be more consistent.” Read more Scripture, pray with greater fervency, love with greater altruism, and so on. But what would such counsel achieve? First of all, it is doubtful that someone predisposed to read the presence of fruit negatively would fare any better in his evaluation simply by increasing effort. But more importantly, such counsel is predisposed to commit the fatal error of viewing the fruit of the faith as the root of faith. It is fundamentally predisposed to appeal to self-justification—something for which we are all hardwired.

The counsel to “do more” in the belief that works provide the ground of assurance rather than the evidence of assurance is the path to legalism—and legalism in its proper sense. In his book The Whole Christ, Sinclair B. Ferguson urges a “gospel logic” to the effect that “there is no assurance of faith that can be experienced apart from faith.”

And it is here that one perceives a counterintuitive counsel that must be given to the one lacking assurance. To look to works (and the counsel to “do more works”) as a means of gaining assurance is essentially counterproductive and pastorally deadly. Only Christ can save us, and assurance, when lacking, must be found by looking to Him. Apart from faith in Christ, no work on our part will assure us of anything except Pharisaism.

Far from being a counsel to laxity, what this counsel intends to secure is an understanding that faith gives rise to obedience rather than obedience’s giving rise to faith. And the difference is crucial. One gives rise to legalism; the other to evidentiary, evangelical (gospel-based) works.

Abiding in Christ

Is not this counsel (to look first to Christ) precisely what Jesus said in His final word to the disciples in the Upper Room?

Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me. I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing. (John 15:4–5) Bearing fruit, something that Jesus identifies as keeping His commandments (15:10), is intimately related to abiding in Him. It is in the sphere of abiding in Christ and not apart from it that fruit emerges.

There is only one cure for a lack of fruit in our Christian lives. It is to go back to Christ and enjoy (yes, enjoy) our union with Him. The “love of Christ controls us” (2 Cor. 5:14). The Greek verb translated here as “controls” is elsewhere rendered as “surrounds” and “hems in” (Luke 8:45; 19:43). That’s what the experience of abiding in Christ does—it hems us in to obedience. From such gracious love, compliance with His commands emerges. Disobedience drives Him away. But when we enjoy His presence, we also desire to “please him” (2 Cor. 5:9). And as we bear the fruit of this union, assurance grows.