Martin Luther on Free Will and the Bondage of the Will

Sect. 167.—I SHALL here draw this book to a conclusion: prepared if it were necessary to pursue this Discussion still farther. Though I consider that I have now abundantly satisfied the godly man, who wishes to believe the truth without making resistance. For if we believe it to be true, that God fore-knows and fore-ordains all things; that He can be neither deceived nor hindered in His Prescience and Predestination; and that nothing can take place but according to His Will, (which reason herself is compelled to confess;) then, even according to the testimony of reason herself, there can be no "Free-will"—in man,—in angel,—or in any creature! 

Hence:—If we believe that Satan is the prince of this world, ever ensnaring and fighting against the kingdom of Christ with all his powers; and that he does not let go his captives without being forced by the Divine Power of the Spirit; it is manifest, that there can be no such thing as—"Free-will!" 

Again:—If we believe that original sin has so destroyed us, that even in the godly who are led by the Spirit, it causes the utmost molestation by striving against that which is good; it is manifest, that there can be nothing left in a man devoid of the Spirit, which can turn itself towards good, but which must turn towards evil! 

Again:—If the Jews, who followed after righteousness with all their powers, ran rather into unrighteousness, while the Gentiles who followed after unrighteousness attained unto a free righteousness which they never hoped for; it is equally manifest, from their very works, and from experience, that man, without grace, can do nothing but will evil!

Martin Luther, Protestant Reformer.  The Bondage of the Will:  Conclusion