What Are the Five Solas, and Why Do They Matter?

What Does It Mean to be Reformed?

One of the common questions that I get as a professor at Reformed Theological Seminary is, What does it mean to be Reformed anyway? Where does that word come from? As might well be known, it actually comes from the Protestant Reformation. The Reformation was a time when the church was reforming itself theologically and doctrinally and even morally, trying to recover some of the core Christian truths that it had always believed. The Reformation was not about creating new truth; it was about recovering truth that had always been there but had been lost.

How do you summarize the Reformation? The Reformers had a way of doing that, and that’s what we now know as the five solas. The word sola is Latin, of course, for the word alone, and there are five alones that Christians have embraced as to what it means to be Christian, what it means to be Reformed, what it means to be an Orthodox believer—particularly coming out of the time of the Reformation.

The first one was first for a reason, which was sola Scriptura, or Scripture alone, which is the belief that Scripture is the highest authority that a person can appeal to. It’s the highest and most ultimate authority in the Christian life, and everything goes back to what the Bible says. By the way, Scripture alone does not mean that Scripture is the only authority; it just simply means it’s the highest authority.

A Biblical-Theological Introduction to the New Testament

Michael J. Kruger

This introduction to the New Testament orients readers to each book’s theology, key themes, and overall message from a Reformed, covenantal, and redemptive-historical perspective—equipping readers to study and teach the New Testament with clarity.

The second sola is faith alone, or sola fide. To say that you believe in faith alone means that justification, the right standing we have with God, does not come from our meritorious work. Righteousness does not come by our contribution to the cause by being a good person, but rather it means that we are justified through the mechanism, through the instrument, of faith alone. It means only faith is the means by which we get Christ, not our own good works.

A third part of the sola is Christ alone (sola Christus). Obviously, Christ is the center of the Reformation. He is, in one sense, the ultimate thing that we put our hope in. To say Christ alone means that his work is sufficient. We don’t need to add to it. We don’t need Christ plus something else. Christ, in all his activity as the God-man in his salvific role, completely achieved our salvation. We don’t need any other person to come alongside Christ to solve that for us, which is very much responding to a lot of the claims of Rome in the time of the Reformation.

A fourth sola is grace alone (sola gratia). This is, of course, central to what the Reformation was all about and central to what it means to be Reformed. When someone says they’re Reformed, some people understand that means that you really believe in what’s known as the doctrines of grace.

The Reformation was not about creating new truth; it was about recovering truth that had always been there but had been lost.

What does that mean? That means that we are saved by God’s own gracious disposition towards us, that he sought us, loved us, died for us while we were still sinners. So it’s not as if God says, “Once you get your act together, once you commit a lot of good meritorious works righteousness, then I’ll decide to love you.” But rather, God loves us on his own will and for his own purposes, and it’s his grace that changes us. God, by his grace, regenerates our hearts so that we might believe. One of the essences of the Reformation is that we don’t believe in order to have a new heart; we have a new heart in order that we might believe. And so we get a new heart so that we can have faith and trust in Jesus Christ. Where does that new heart come from? God’s gracious work through the Holy Spirit.

The last sola is for the glory of God alone, soli Deo gloria. This is the idea that all of the Christian life is set up not for our own glory and not for the glory of individuals or even the glory of the church, but ultimately for the glory of God. Whatever a Christian does, whether it’s something we would consider a religious activity or what we would consider a secular activity (although those categories are not categories the Bible really recognizes), that all our activities are ultimately for God’s ultimate glory.

Those five things are known as the five solas. That’s what it means to be Reformed. That’s what it means to have orthodox Protestant theology coming out of the time of the Reformation.

Michael J. Kruger is the author of A Biblical-Theological Introduction to the New Testament: The Gospel Realized.



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