As noted when thinking about sola scriptura, most religions and religious movements have formal and material principles from which authority is derived and by which doctrines are summarized, respectively. Usually the formal principle is a text(s)—hence sola scriptura is the formal principle of the Reformation—while material principles tend to be the summary or central teaching(s) of the religion or the movement. The material principle of the Reformation is the next sola under consideration: sola fide. This no doubt was what Luther was getting at when he called justification by faith articulus stantis aut cadentis ecclesiae-the point of belief which determines whether the Church stands or falls. Likewise, G.C. Berkhouwer:
The confession of divine justification touches man’s life at its heart, at the point of its relationship to God. It defines the preaching of the Church, the existence and progress of the life of faith, the root of human security, and man’s perspective for the future.
Sola fide is the teaching that justification is by faith alone as opposed to faith and works. Thus, this sola specifically relates to the doctrine of justification. Justification before God, the reformers came to understand and rediscover, is by faith alone.
For by grace—sola gratia—you have been saved through faith—sola fide—. And this is not your own doing; it is the gift of God, not as a result of works, so that no one may boast (Eph. 2:8-9).
As noted last week when we considered sola gratia, salvation is not a demand but a donation from God— “it is the gift of God” (Eph. 2:8). At the heart of all this was Luther’s wrestling with Roman 1:17 and what was meant by the phrase “the righteousness of God.”
For I am not ashamed of the gospel, for it is the power of God for salvation to everyone who believes, to the Jew first and also to the Greek. For in it the righteous of God is revealed from faith to faith, as it is written, “The righteous shall live by faith.” (Rom. 1:16-17)
Paul’s progression of thought can be clearly seen when we remember that both the English word “for” and the Greek word behind it gar mean here something like, “because.” His train of thought actually goes back to 1:15. Notice how it unfolds:
So I am eager to preach the gospel to you also who are in Rome (1:15). Why is that Paul? Because I am not ashamed of the gospel (Rom. 1:16). So you’re eager to preach because you’re not ashamed of it. Why aren’t you ashamed of it? Because it is the power of God for salvation to everyone who believes, to the Jew first and also to the Greek (Rom. 1:16). How is this possible? How can this gospel bring salvation to the whole world? Because in it the righteous of God is revealed (Rom. 1:17).
And this righteousness of God which was for so long elusive to Luther, he came to understand was offered freely to all and received simply by faith: from faith to faith, as it is written, “The righteous shall live by faith (Rom. 1:17). The Westminster Shorter Catechism Question and Answer #86 summarizes it this way:
What is faith in Jesus Christ?
Faith in Jesus Christ is a saving grace, whereby we receive and rest upon him alone for salvation, as he is offered to us in the gospel.
Sinners look to a righteous savior who became a sinner so that we might become righteous. As Luther noted, Christ became “the greatest transgressor, murderer, adulterer, thief, rebel, blasphemer, etc. that ever was.”
We are sinners and thieves, and therefore guilty of death and everlasting damnation. But Christ took all our sins upon him, and for them died upon the cross … all the prophets did foresee in spirit, that Christ should become the greatest transgressor, murderer, adulterer, thief, rebel, blasphemer, etc. that ever was … for he being made a sacrifice, for the sins of the whole world, is now an innocent person and without sins … our most merciful Father, seeing us to be oppressed, overwhelmed with the curse of the law, and so to be holden under the same that we could never be delivered from it by our own power, sent his only Son into the world and laid upon him all the sins of all men, saying: Be thou Peter that denier; Paul that persecutor, blasphemer and cruel oppressor; David that adulterer; that sinner which did eat the apple in Paradise; that thief which hanged upon the cross; and, briefly, be thou the person which hath committed the sins of all men; see therefore that thou pay and satisfy for them. Here now cometh the law and saith: I find him a sinner, and that such a one as hath taken upon him the sins of all men, and I see no sins but in him; therefore let him die upon the cross. And so he setteth upon him and killeth him. By this means the whole world is purged and cleansed from all sins, and so delivered from death and all evils. — Martin Luther.
This is why justification is so liberating. This is why it makes the soul sing. And this is why sola fide became known as the material principle of the Protestant Reformation.