Once Luther was hijacked to be put into quarantine on the Wartburg, he did not fall into despair, but into a working frenzy. Astounding, what he produced and that despite heavy attacks by his relentless foes and his urge to fight back. He thought, that this retaliation was basically a waste of time, because his enemies were careless, not really up to the challenge and far too easy prey. That´s why later, he was so thankful for Erasmus of Rotterdam to put the real and sticky issues on the table with the matter of so-called “free-will”. But that was later.

For now, Luther tackled the many arising issues, partly out of Christian responsibility to correct failing, incompetent and erring brothers, but mainly to help a rather disoriented public to find a faithful way in the stormy seas – navigating between the Scylla of legalistic self-righteousness and the Charybdis of libertine desperation.
Justus Jonas Latomus
One of the guys he tackled during his stay on the Wartburg was the Belgian professor at Louvain (Universität Löwen) – Jacobus Masson (1475-1544) – called Latomus. Luther´s response is remarkable for its clarity, precision and eloquence – despite serious limitations not having a meaningful library. Still, he hit the mark, and this became one of his standard papers on Justification etc. No small wonder, that Professor Dr. Gottfried Hoffmann used it as a standard research project for students in the preparatory courses on Lutheran Dogmatics (Proseminar).
Let´s hear from Luther himself – first in a German reading based on the German translation by Rudolf Mau – and then looking at the English translation prepared by Dr. George Lindbeck of Yale Divinity School and to be found in Luther Works Volume 32 – starting on Page 137…
We start with Luther´s introduction and dedication to his colleague Justus Jonas – Propst des Wittenberger Kirchenkollegiums…
AGAINST LATOMUS
Luther’s Refutation of Latomus’ Argument on Behalf of the Incendiary Sophists of the University of Louvain (1521)
To the Honorable Justus Jonas, (Dean of the Clergy) of Wittenberg, my superior in the Lord, I, Martin Luther, send greetings in the Lord.
LW 32: 137-140
I also, my good Jonas, would like to congratulate you on the office you have recently assumed. Unable to be present in person, I have decided to send you this “Latomus” of mine. He is no longer a detractor of linguistic competence. You need not fear him, for that Ishbibenob has been vanquished by the strength of our Abishai [2 Sam. 21:16–17]. Neither is he the tardy advocate justifying the crime of the Louvainian arsonists with a malicious pretense of modesty and an unfortunate verbal subtlety. Nor is he the one whom you have seen glorying in the lord pope and his bull. But, I send you a “Latomus” who—purified by Luther’s holy water—seems to be freed from the ghosts and hobgoblins with which until now he has been disturbed, and with which he was wont to trouble devout hearts.
If the Louvainians had published their opinion at the proper time and, as is proper for learned men, had consulted together before acting, they would neither have condemned nor destroyed my writings, nor would they like fools seek to justify themselves only after the deed. This much I hope to show. Latomus’ book certainly shows me how easy it is to sit in one’s corner and babble against an absent Luther: “This is heretical, this is erroneous.” But in public they would not have had confidence in their strength and daring to deal with the matter. This persuades me that if the bull had not inflated Latomus’ confidence he would never have published his illustrious “Argument.” Therefore he boasts as of a deed well done and, dreaming of the bull’s antique and antiquated terrors, believes that his booklet will alarm the world. For this reason he now fearlessly dares to play against Luther with God’s mighty Scriptures. I’d just as soon have such an act approved by such a bull. I would not want it otherwise than to be condemned by such a bull. The bull, indictment, judge, and advocate all agree beautifully. May the Lord Jesus protect me and all devout souls from their contagion and their company! Amen.
Truly it won’t be easy for you to believe how unwillingly I have torn myself away from the peace-giving words of Christ, with which I have been occupied on this my Patmos, in order to waste my time reading the nonsense of this prickly and thorny sophist. Indeed, the man is sophistic from the sole of his foot to the crown of his head. Swollen with the flatulent bull, he writes with such confidence that he considers both industry and discernment unnecessary. He is content to babble whatever he has read or swallowed. It is a great bother to reply to him, for in doing so you can neither exercise skill nor increase your learning, and yet you are forced to waste precious hours. I suspect the man of believing that Luther has been spirited away or has been condemned to eternal silence so that they may once again freely dominate the public with sophistic tyranny. They consider me not a little guilty for its decline and fall. O that its downfall were complete; I would gladly be guilty, even unto death, of this seven times unforgivable sin (if we are to believe the most holy priests of the bull).
However, I am concerned that while we bravely battle over grace and good works, we do not in the meantime deprive ourselves of grace or of works. When I consider these fearful times of wrath, I ask only that my eyes become fountains of tears so that I may bewail this latest desolation of souls [Jer. 9:1] which this reign of sin and of perdition is producing. Seated in Rome in the midst of the church [2 Thess. 2:4], this monster vaunts itself as God, is flattered by the bishops, compliantly aided by the sophists, and there is nothing that the hypocrites are not willing to do for it. “Therefore hell has enlarged its appetite and opened its mouth without any bounds” [Isa. 5:14], and Satan plays at the damnation of souls. There is no one among us who, seriously and with tears, stands in this day of fury and builds up a wall for the house of Israel [cf. Jer. 9:1; 15:20]. So, full of anger against blasphemers like Latomus, who deal sophistically with serious matters and compel us to interrupt better tasks in order to concern ourselves with their senseless insanities, I invoke these words against their flinty foreheads: “All my enemies shall be ashamed and sorely troubled; they shall turn back, and be put to shame in a moment” [Ps. 6:10].
In order not to detain you with too long a letter, I shall answer the main points of Latomus’ preface in a separate introduction. Meanwhile accept this testimony of my esteem for you and ask the Lord for me that I may be delivered (for so I now dare to pray with the Apostle) from the evil and unbelieving men [2 Thess. 3:2; cf. Rom. 15:31] who inhabit this Babylon, and that a door be opened to me [Col. 4:3] for the praise of the glorious grace of the gospel of His Son [Eph. 1:6]. I, for my part, pray the Lord to give you His Spirit so that you may lecture on those most pestilent decrees of the Antichrist, which you are commissioned to teach, with the purpose of which I have told you; may you be an Aaron clothed in holy garments—that is, armed with the sacred Scriptures—so that, grasping the censer of prayer [Rev. 8:3] you may go forth to encounter this devastator in the midst of the Romish fire which now consumes the world. It is soon to be extinguished by another fire coming from heaven at the advent of our Savior, for whom we wait. See to it, my brother, that you teach so that what you are teaching must be forgotten, and that [your students] know that they must flee as something deadly whatever the pope and papists hold and assert. Since we do not have the power to abolish this public and world-wide evil, and are compelled to administer the sacrilegious provinces of Babylon, it remains for us so to administer them as to recognize that they are completely different from Jerusalem our home, and that they are its adversaries, ravagers, and enemies of insatiable cruelty. Thus we shall not smile and caress our bondage as do those who perish, in whom the gospel of the glory of God is hidden [2 Cor. 4:3]. Do not lightly regard your ministry for, alongside the poisonous refuse and insane foolishness of the pope, you present the saving and life-giving gospel of Christ. Thus young men may have an antidote against this venom—the mere smell of which kills a man—until such time as they learn to reject evil and choose the good for themselves. This Immanuel is commended to you [cf. Isa. 7:14]. Therefore be hardy and strong. Do not fear this Baal-peor [Num. 25:3] for if we only believe, it is scarcely a Baal-zebub [2 Kings 1:2]—that is, a man of flies. For we believe that Jesus Christ is the Lord, blessed in eternity—Amen!—who will perfect and confirm you and his little church which is with you. Be strong in Him.
In the place of my exile, June 8, 1521.