On the Bondage of the Will (Latin: 'De Servo Arbitrio', literally, "On Un-free Will", or "Concerning Bound Choice"), by Martin Luther, was published in December 1525. It was his reply to Desiderius Erasmus's De libero arbitrio diatribe sive collatio or On Free Will, which had appeared in September 1524 as Erasmus's first public attack on Luther, after being wary about the methods of the reformer for many years. At issue was whether human beings, after the Fall of Man, are free to choose good or evil. The debate between Luther and Erasmus is one of the earliest of the Reformation over the issue of free will and predestination. (Summary by Wikipedia)