Luther and Calvin on the Assurance of Your Salvation

This past January, I suffered a retinal detachment in my right eye. For those unfamiliar with this injury, it involves a drastic loss of vision in the affected eye—from perfect sight to total blindness—usually within one to two days. As I was rushed into surgery to save my vision, the hospital staff asked me two unsettling questions: “Do you have a living will?” and “Do you accept this procedure may result in death?”

A low probability for sure, but facing my own mortality was not something I had considered thirty-six hours earlier. While I dwelt upon these questions, I found myself tempted by two more: If I were to die today, am I confident I would join Christ in heaven? Or is there a chance that my sins are still unforgiven?

The Modern Problem of Assurance

My fears had exposed hidden doubts of the believer’s assurance of salvation, a doctrine Charles Ryrie defines as “the realization that one possesses eternal life.” A Christian is assured of their salvation when they are confident God has forgiven their sins through Christ’s death and resurrection. Why, then, do so many believers doubt or lack a confident assurance?

For me, this lack of assurance resurfaced as a result of a faulty understanding of how assurance is received. Some well-meaning preachers had taught me to, “look into my heart and examine my works,” to assure myself of salvation. Since the Holy Spirit indwells all believers, they reasoned, my transformed heart and righteous works would attest to the reality of my saving faith.

Despite these admonitions, however, I found myself conquered by uncertainty when I looked inward. Both my heart and my works condemned me before God. No matter how small my sin—nor great my righteousness—guilt burdened my soul. As I looked to myself for assurance, I found only doubt; a doubt which, in the hours approaching my surgery, brought me to the point of despair.

Thankfully, during this time of doubt, I remembered the writings of two Reformation theologians: Martin Luther and John Calvin. Rather than pointing believers towards themselves for assurance, these reformers directed them to Christ—the one who gives true assurance to restless souls.

Luther on Assurance

In July of 1530, Martin Luther penned a letter to his dear friend, Jerome Weller. During a season of depression, Weller began to doubt the reality of his salvation, and as a result, he became overwhelmed by the prospect of hell. Reassuring Weller of his saving faith, Luther wrote, “When the devil throws our sins up to us and declares we deserve death and hell, we ought to speak thus: ‘I admit  I deserve death and hell. What of it? Does this mean I shall be sentenced to eternal damnation? By no means. For I know One who suffered and made satisfaction in my behalf. His name is Jesus Christ, the Son of God. Where he is, there I shall be also.’”

Like Weller, my fears concerned death and hell; and rightfully so, as Scripture teaches all humans are sinful and our sin merits both physical and eternal death (Rom 3:23; 6:23; Matt 25:46). Luther, however, aware of these truths, exhorts us to admit our sinfulness and own the consequences; we are sinners and we do deserve death and hell – what of it? Our guilt before God is not the end of the story.

You see, Luther also reminds us our assurance of salvation is tied to Christ and our unbreakable union with him (Rom 8:1; Eph 1:3; Col 1:27). Jesus Christ suffered and made satisfaction on our behalf, was raised from the dead, and has unified us to himself through faith in his death and resurrection (2 Cor 5:21; 1 Cor 15:3–4; Eph 1:13–14; John 3:16). Because of these gospel truths, when I felt tempted to doubt my assurance of salvation on the day of my surgery, I was able to dwell on my unity with Christ and confidently declare, “I know One who suffered and made satisfaction in my behalf. His name is Jesus Christ, the Son of God. Where he is, there I shall be also.”

Calvin on Assurance

Alongside the writings of Luther, in the days following my surgery I found myself refreshed by John Calvin’s Institutes of the Christian Religion. As I struggled to find assurance through the examination of my works, Calvin encouraged me to cease the practice entirely. In Institutes, he wrote, “For nothing so moves us to repose our assurance and certainty of mind in the Lord as distrust of ourselves, and the anxiety occasioned by the awareness of our ruin” (3.2.23). And again later: “For faith totters if it pays attention to works, since no one, even of the most holy, will find there anything on which to rely” (3.11.11).

Like Luther, Calvin was acutely aware of the sinful state of humankind (Rom 3:9–18). In light of this widespread sinfulness, he taught that every person stands guilty before God (Rom 3:19). This means that when we compare our works to the perfect standard of God’s law, we will only remind ourselves of our deserved condemnation (Rom 3:20). As a result, if we seek assurance by looking to our works, we will find only doubt. Calvin, however, did not stop after his exhortation to distrust works for assurance. Rather, alongside Luther, he directs us to the true source of assurance—Jesus Christ.

Calvin testifies:

But since Christ has been so imparted to you with all his benefits that all his things are made yours, that you are made a member of him, indeed one with him, his righteousness overwhelms your sins; his salvation wipes out your condemnation; with his worthiness he intercedes that your unworthiness may not come before God’s sight. Surely this is so: We ought not to separate Christ from ourselves or ourselves from him. Rather we ought to hold fast bravely with both hands to that fellowship by which he has bound himself to us (3.2.24).

Calvin reminds us we can confidently hold to our assurance of our salvation because of our unity with Christ (Col 1:27). As the firstborn of many brothers and sisters, Christ shares his heavenly inheritance with all who place faith in his death and resurrection for the forgiveness of sins (Rom 8:29; Eph 1:11; 1 Cor 15:3–4). As his co-heirs, Christ has united us to himself through faith, making us partakers in every portion of his heavenly inheritance; most importantly of all, his righteousness overwhelms our sins, his salvation wipes out our condemnation, and his worthiness intercedes on behalf of our eternal life (Eph 1:3–14; Rom 8:1; Rom 8:34).

Because of these gospel truths, when we feel tempted to doubt our assurance of salvation, we can remind ourselves that we have been unified to Christ as his co-heirs and we “ought to hold fast bravely with both hands to that fellowship by which he has bound himself” to us.

Nine months removed from my retinal detachment surgery and my sight has been restored. This experience has taught me that while good works play an important role in the Christian life (Eph 2:10), relying upon them for assurance will cause only doubt. Like Luther and Calvin, believers should turn towards their unity with Christ for a confident faith. In the same way, all believers need to clearly see their hope in Christ when they find themselves in doubt about their assurance of salvation.

What can you do?

1. Don’t trust yourself or your works for assurance of salvation. Since mankind is both sinful and guilty before God, measuring your works against the perfect standard of God’s law will only lead to doubt, not assurance (Rom 3:9–18; Rom 3:19; Rom 3:20).
2. When you are tempted to doubt your assurance of salvation, turn to Christ and your unity with him (Col 1:27; Col 3:3–4). If you believe in Christ’s death and resurrection for the forgiveness of sins, then you are unified with him as his co-heir and all of his heavenly inheritance, including eternal life, belongs to you (1 Cor 15:3–4; Eph 1:3–14; John 3:16).
3. Memorize Martin Luther’s words to his friend, Jerome Weller: “I know One who suffered and made satisfaction in my behalf. His name is Jesus Christ, the Son of God. Where he is, there I shall be also.”

About the Contributors

Keith S. Lindley

Keith S. Lindley (ThM, 2016) is currently pursuing a PhD in Theological Studies at DTS. He is an ordained pastor, a missionary, and an active member of Stonebriar Community Church in Frisco, Texas. He also serves as an instructor of Bible and theology at the Opened Bible Academy. His main research interests include theology, philosophy, and the intersection between faith and popular culture. He and his wife, Megan, live in Plano, Texas with their daughter, Ava, and their dogs, Fitz and Faith.