In his treatise on “The Freedom of the Will,” (1524) even though Erasmus did not know what God was doing above him he insisted on attempting an ascent into the hidden mysteries of God to argue for human choice. Erasmus’s conclusion was that if God was truly almighty and immutable then God must also be in control of all things. Logic in this case led Erasmus to an unacceptable conclusion: God must therefore cause sin and evil, suffering and death. But this could not be the case. So, in opposition to logic, Erasmus looked for a way to insert a little bit of freedom for the sake of morality. As he wrote:
The law of works, on the other hand, commands and threatens punishment. It doubles sin and engenders death, not that it is evil, but because it commands actions which we cannot perform without grace. The law of faith commands more arduous things that the law of works, yet because grace is plentifully added to it, not only does it make things easy which of themselves are impossible, but it makes them agreeable also. Faith, therefore, cures reason, which has been wounded by sin, and charity bears onward the weak will… For although free choice is damaged by sin, it is nevertheless not extinguished by it. And although it has become so lame in the process that before we receive grace we are more readily inclined toward evil than good, yet it is not altogether cut out, except that the enormity of crimes which have become a kind of second nature so clouds the judgment and overwhelms the freedom of the will that the one seems to be destroyed and the other utterly lost. (Rupp, “Luther and Erasmus,” 50-51.)
Luther wrote in response:
On the authority of Erasmus, then, free choice is a power of the will that is able of itself to will and unwill the word and work of God, by which it is led to those things which exceed both its grasp and its perception. But if it can will and unwill, it can also love and hate, and if it can love and hate, it can also in some small degree do the works of the law and believe the gospel. For if you can will or unwill anything, you must to some extent be able to perform something by that will, even if someone else prevents you completing it. Now, in this case, since the works of God which lead to salvation include death, the Cross, and all the evils of the world, the human will must be able to will both death and its own perdition. Indeed, it can will everything when it can will the word and work of God; for how can there be anything anywhere that is below, above, within, or without the word and work of God, except God himself? (Rupp, “Luther and Erasmus,” 173.)
The logic of human freedom in Erasmus’s argument was quite illogical to Luther. Erasmus’ opinion finally made free will a faith in one’s own self. Erasmus did not trust God to be God unless something was left for human responsibility, so God would be free from guilt for causing suffering and evil. Erasmus’ assertion of freedom was the bondage of the will.
For Luther, however, the solution was not to preserve the human responsibility for sin and evil. In his first thesis at Heidelberg, Luther understood that was not an option since even what is best in old human life is now removed as a means of salvation by Christ’s Cross. Instead of human responsibility Luther moved to the Holy Spirit and the proclamation of the Gospel.