In the end, one little word divided the churches of the Reformation and the Roman Catholic of the sixteenth century. To borrow Luther’s language in his great Reformation hymn, “one little word felled” the corrupt Roman Catholic institute of his day. That one little word was “only,” or as it is in Latin, sola. The Reformers said “only” or “alone,” while Rome consistently said “and.” The Reformers included the word “only” in especially five important doctrines that they taught. These five statements gradually became known as the “five solas.

The Reformers said that the authority in the church is sola Scriptura, that is, Scripture alone. Rome said that the authority in the church is Scripture and tradition. The Reformers said that Christ is our only Mediator, solus Christus. Rome said that men have many mediators: Christ and angels, saints, and the Virgin Mary. The Reformers said that we are saved by grace alone, sola gratia. Rome said that we are saved by grace and on account of human merit. The Reformers said that we are saved by faith only, sola fide. Rome said that we are saved by faith and by our own works and free will. The Reformers said soli Deo gloria, to God alone be the glory. Rome said, in effect, that the glory for salvation is partly due to the grace of God and partly due to the sinner. Throughout, Rome insisted not on “only” or “alone,” but on “and.”

Still today, this is the one little word that distinguishes the churches that are faithful to the Reformation from the Roman Catholic Church. At the same time, this is an indicator that a church has departed, as well as the degree to which it has departed, from the Reformed faith. Is it maintaining the word “only” in the same areas and with the same tenacity as the Reformers did? If not, it has not only departed from its Reformation heritage, but it is on the slippery slope that leads back to Rome. So serious a matter are the five solas!

The five solas encapsulate the Reformation. They demonstrate what the Reformation was about and why the Reformation was necessary. From five points of view, they summarize the gospel that was restored to the church through the Reformation. And they provide the rationale for the Reformation. They account for the tremendous sacrifices that Reformed believers then and now are willing to make, even “letting goods and kindred go, this mortal life also.” So highly did the Reformers and the churches of the Reformation value these five doctrines and the pivotal place they occupied in the life of the church. Do we value them as highly as they did?

Sola Scriptura

All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: that the man of God may be perfect, throughly furnished unto all good works (II Tim. 3:16, 17).

The first of the five solas is sola Scriptura, Scripture alone. The Reformers taught that Scripture alone is the final authority. No one and nothing are above Scripture, nor may be placed as an authority alongside of Scripture. Scripture is the authority for the individual believer, as well as for the church as a whole. It is the authority over faith, what we believe, and it is the authority over practice, how we live our daily lives. Scripture is also determinative for the worship of the church, so that every element of worship is to be derived from Scripture.

The Reformers rejected Rome’s elevation of other authorities alongside the authority of Holy Scripture. Rome taught that the Bible is an authority in the church, in fact, a very important authority in the church. But the Bible is not the only authority. The authority in the church is the Bible and tradition, which tradition includes the writings of the church fathers, the decisions of the churches councils, the decrees of the pope, and the writings that the Roman Catholic Church added to the Bible known as the Apocrypha.

When the Reformers insisted that the Bible alone is the final authority in the church, they did not reject tradition altogether. In fact, the Reformers had the highest regard for church tradition, as well as for the decisions of many past church councils, like Nicea and Chalcedon. But they honored tradition only in so far as tradition agreed with Scripture.

The Reformers honored Scripture as the highest authority because they believed the Bible to be the divinely inspired Word of God. Scripture is the authority in the church because Scripture alone is the very Word of God. Thus, it is capable of functioning as the supreme authority in the church.

Sola Scriptura is the first sola for good reason. All the other solas depend on the first sola. They are all derived from sola Scriptura. Scripture teaches that Christ is the only Savior. Scripture teaches that salvation is by grace alone, through faith alone. And Scripture teaches that to God alone must be all the glory. If Scripture is not the only authority, the other four solas fall to the ground.

I am bound by the Scriptures and my conscience is captive to the Word of God. I cannot and I will not retract anything, since it is neither safe nor right to go against conscience. I cannot do otherwise, here I stand, may God help me. Amen. (Martin Luther, “Luther at the Diet of Worms,” in Luther’s Works: The Career of the Reformer, 32:112-3.)

Solus Christus

For there is one God, and one mediator between God and men, the man Christ Jesus (I Tim. 2:5).

The Reformers insisted that Scripture proclaims Christ as the only Savior of sinners. As one with the Father, the very Son of God, He does everything that is necessary for our salvation. Jesus leaves nothing undone or partially done, so that we need other saviors and additional mediators alongside of Him. Christ’s saving work was complete and effectual. He accomplished everything on account of which He had been sent into the world by the Father.

Because Jesus is the only Savior, who has fully accomplished all of our salvation, the Reformers objected to the Roman Catholic doctrine of the mass as a perpetual re-sacrificing of Jesus, and the doctrine of transubstantiation, which was necessary for the re-sacrificing of the body and blood of Jesus. Such a sacrifice is not only unnecessary, but is a blasphemous denial of the finished work of Christ and an accursed idolatry. Thus the Reformers swept away not only the mass, but the whole Romish priesthood, which priesthood was necessary for the re-sacrificing of the body and blood of Jesus. The finished work of Christ, our great and only High Priest, fulfilled all the sacrifices of the Old Testament and eliminated any further need for a priesthood. Rome’s priesthood, with its sacrifice of the mass, is a perpetual and public denial that Christ alone is our Savior.

Jesus’ merits are the only propitiatory merits that take away both the guilt and the punishment of our sins. Rome taught that the merits of the saints, and especially the merits of the Virgin Mary—merits that had accumulated through their works of supererogation—are merits that are at the disposal of the church. The church distributes these merits through the purchase of indulgences. Or there were indulgences to be earned simply by paying to observe all kinds of relics of the saints, collections of which could be found in every major city throughout Europe in the sixteenth century. The Reformation demolished the whole system of indulgences on the basis of the truth that Jesus is the only Savior. His merits alone, no other merits, are the basis for our salvation.

In short, whoever wraps up two kinds of righteousness [Christ’s and our own] in order that miserable souls may not repose wholly in God’s mere mercy, crowns Christ in mockery with a wreath of thorns. (John Calvin, Institutes of the Christian Religion, ed. by John T. McNeill, 3.11.13; 1:743.)

Sola gratia

For by grace are ye saved through faith; and that not of yourselves: it is the gift of God; not of works, lest any man should boast (Eph. 2:8, 9).

The Reformation, like the gospel, proclaimed the grace of God. Salvation is by grace, has its source in grace, and is the ultimate expression of God’s grace. God saves those who are undeserving of salvation and unable to accomplish their salvation. Salvation is from beginning to end the work of God alone. Sinners are saved, are the passive recipients of salvation, and receive salvation from God. Salvation is not earned, but is a gift of God that is freely given.

That salvation is by grace is due to the fact that the source of salvation is in the eternal will of God. Not the free will of the sinner, but the sovereign will of God is the cause of salvation. That is the ultimate reason on account of which salvation is by grace. The Reformers taught the truth of predestination—double predestination, both election and reprobation. Although a number of early church fathers taught predestination, over time prominent Roman Catholic theologians had buried the doctrine; some even openly opposed it. Luther, Calvin, and the other Reformers restored to the church the truth of sovereign predestination. Because salvation has its source in God’s everlasting counsel, salvation is clearly gracious.

Over against the teaching of sola gratia, Rome taught that the salvation of sinners is due, at least in part, to merit. We are saved by grace, but not by grace alone. The grace of God cooperates with man, so that salvation is due partly to the grace of God and partly to human merit. That may be the sinner’s own merit or the merits of the saints, which merits are available through purchase from the church. The Reformers rejected this teaching. They asserted that salvation is monergistic, not synergistic; it is the work of God alone, not God and man.

They who assert free will are denying Christ. For if it is by my own effort that I obtain the grace of God, what need have I of the grace of Christ in order to receive it? Or what do I lack when I have the grace of God? (Martin Luther, The Bondage of the Will, in Luther’s Works: The Career of the Reformer, 33:279.)

Sola fide

Therefore we conclude that a man is justified by faith without the deeds of the law (Rom. 3:28).

Salvation is by grace alone, through faith alone. Faith is the instrument, the “alone instrument,” to use the language of the Westminster Confession of Faith (WCF, 11.2). The righteousness on account of which we are righteous before God is not an innate righteousness. The righteousness on account of which we are righteous before God is not an acquired righteousness. But the righteousness on account of which we are righteous before God is the imputed righteousness of Jesus Christ. That righteousness is ours by faith and by faith alone.

Rome taught that we are righteous before God partly by faith. Righteousness is ours by faith and by the works of faith. Faith and the good works that faith produces together constitute our righteousness before God. The Reformers rejected Rome’s teaching about faith and insisted that we are righteous by faith alone. Well known is the controversy that Luther raised when his German translation of the Bible appeared in print. Luther translated Romans 3:28 by adding an “alone” that is not in the original text. His translation was: “Therefore we conclude that a man is justified by faith alone, without the deeds of the law.” Luther knew very well that “alone” was not found in the original and that his insertion could not be justified by an appeal to the text. At the same time, although he had transgressed the boundaries of a faithful Bible translator, there is good reason for Luther’s insertion because of the sense of the passage. As Luther pointed out, by contrasting as he does faith and the deeds of the law, and by insisting that we are righteous by faith and not by the deeds of the law, Paul is teaching justification by faith alone.

What underscores the truth that we are righteous by faith alone and not by our own works is the truth that even the faith by means of which we are justified is the gift of God. He gives and He works faith in the elect. That is grace!

You farther see how faith and the merits of works are contrasted, as things altogether contrary to each other. As then trust in works is the chief hindrance, by which our way to obtain righteousness is closed up, it is necessary that we should wholly renounce it, in order that we may depend on God’s goodness alone. (John Calvin, Commentary on the Epistle of Paul the Apostle to the Romans. Comments on Romans 9:32.)

Soli Deo gloria!

For of him, and through him, and to him, are all things: to whom be glory forever. Amen. (Rom. 11:36)

The Reformers taught Scripture alone, Christ alone, grace alone, and faith alone because they had a zeal for the glory of God alonesoli Deo gloria! They understood this to be the overarching teaching of Scripture. They saw this to be the great goal of the saving work of Christ. And they were convinced that this was the purpose of salvation by grace and through faith, that God, and not any man, must be glorified—God alone!

For this reason they objected to Rome’s teaching of merit and works-righteousness. It gave the glory for salvation, at least in part, to the sinner himself. For this reason, they objected to the papacy. Not so much that it introduced hierarchy into the church, although it did. But more seriously, the papacy attributed to man the glory that is due to God alone.

God is to be glorified for salvation, not only by performing certain rituals and rites, but by an entire life lived to the glory of God. The apostle says in II Corinthians 10:31, “Whether therefore ye eat, or drink, or whatsoever ye do, do all to the glory of God.” That is the Christian life and the Reformed view of the Christian life: soli Deo gloria!

The Gospel proclaims the glory of God alone. It follows that we are foolish and lost sinners, because the glory of God is not set forth unless we ourselves are confounded. The papists do not want this confounding, yea, they ascribe a part of righteousness to their own glory, and therefore they cannot bear the Gospel. It is the office of an evangelical preacher to proclaim the glory of God alone. (Martin Luther, “Lecture on Isaiah 49:3,” in Luther’s Works: Lectures on Isaiah Chapters 40-66, 17:172.)