As the Reformation was "the offspring of the age," so the leading doctrine of the Reformation, i.e., Justification by Faith, was the logical deduction from the promises laid down by the age. And in view of the times and the events, it is difficult to conceive any other doctrine that might properly have been the leading one.
At the date of the Reformation, the beginning of the six teenth century, the papacy had, from Gregory the Great, through Azcharias and Stephen III., Hildebrand and Innocent III., Alexander VI, and Leo X., reached that pinnacle of abu sive power where she held the sway over this world and the world to come, and over the eternal destinies of the human race; and where she could traffic in immortal bliss, selling it for money, where, in the energetic words of another,
The church was omnipotent, and Leo was the church. (Historical Studies, Eugene Lawrence, 1876)
In the exercise of that omnipotency, Leo proceeds to the sale of indulgences, covering both worlds for the past, present, and future. And now begins the Reformation. Luther resists the sale of indulgences, and the claims upon which they are sold. It is plain that if both sides stand firmly to their principles, nothing else can come out of it but renunciation of the church of Rome, on the part of Luther, the adoption of Christ as Head of the church instead of the pope, and justification by faith instead of by money in the purchase of indulgences. For:
1. If the pope cannot grant remission of sin by an indulgence, can he grant remission at all?
2. If he cannot grant remission at all, can he bestow upon another the power to remit sin?
3. If he has not the authority, and those who receive authority from him have it not, then is such authority possessed by any one on earth?
4. If it stand thus with the pope, is he head of the church?
5. If he be not the head of the church, is not Christ alone the head of the church on earth as well as in heaven?
6. If Christ alone be the head of the church and the one alone through whose intercession and merits forgiveness of sin can be obtained, and if this forgiveness is to be obtained from God alone, through Christ alone, without the intervention of priest, bishop, or pope, must not every one go to Christ himself, for himself, for justification?
And therefore the logical consequence is justification by faith.
And such was the course through which Luther was led. Not that Luther saw or realized it all when he began. Not at all. Had he realized even the half of it, doubtless he would have stood aghast. When he opposed the indulgences, he saw only the wickedness of the indulgences as ministered by their vendors, and of the manner in which Tetzel conducted the traffic. And as the pope persisted in this course, and Luther persisted in his opposition, this first step carried him logically to the second, and, as events shaped the course, finally to the logical consequence of all, justification by faith, and therefore the Reformation.