Theology of Martin Luther

The theology of Martin Luther was instrumental in influencing the Protestant Reformation, specifically topics dealing with Justification by Faith, the relationship between the Law and the Gospel (also an instrumental component of Reformed theology), and various other theological ideas. Although Luther never wrote a "systematic theology" or a "summa" in the style of St. Thomas Aquinas, many of his ideas were systematized in the Lutheran Confessions.

"This one and firm rock, which we call the doctrine of justification," insisted Luther, "is the chief article of the whole Christian doctrine, which comprehends the understanding of all godliness."Lutherans tend to follow Luther in this matter. For the Lutheran tradition, the doctrine of salvation by grace alone through faith alone in Christ alone is the material principle upon which all other teachings rest.

Luther came to understand justification as being entirely the work of God. Against the teaching of his day that the believers are made righteous through the infusion of Gods grace into the soul, Luther asserted that Christians receive that righteousness entirely from outside themselves; that righteousness not only comes from Christ, it actually is the righteousness of Christ, and remains outside of us but is merely imputed to us (rather than infused into us) through faith. "That is why faith alone makes someone just and fulfills the law," said Luther. "Faith is that which brings the Holy Spirit through the merits of Christ". Thus faith, for Luther, is a gift from God, and ". . .a living, bold trust in God's grace, so certain of God's favor that it would risk death a thousand times trusting in it." This faith grasps Christ's righteousness and appropriates it for itself in the believer's heart.

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