Luther sends him his interpretations of the first book of Moses as a token of his gratitude, it seems, for medical services.
The original is in the Pauline Library at Münster and is pasted on the inside page of the book: In primum librum Mose enarrationes Reverendi Patris D.. D. Lutheri etc. On the title page below is written by Luther's hand: Clarissimo Viro D. Johanni Magenbuch Medicinarum Doctori, Suo Amico Martinus Luther dd. Printed in Seidemann, Lutherbriefe, p. 68 f. (wrong: 86).
Grace and peace! I have never written to you, respectable doctor, although my conscience has often reproached me that I owe you no small debt of gratitude for your special and manifold benevolence and the kindness with which you have so generously and most willingly spent everything you could on me at all times. But since there was nothing that I could have given in any way as a reward, and it is not proper (as Aristotle says) for old people to set aside respect, therefore you will forgive my immanence or ingratitude, or whatever fault you may hold me guilty of. For I have always been exceedingly grateful to you from the bottom of my heart, God knows that. But so that I would not be completely nothing with you, since you do not need gold, and I do not have it either, I am sending you this Moses of mine, that is, Genesis, which I have laid out publicly in our school, as much as God has given me grace, as a memorial to our friendship and my grateful remembrance of your good deeds.
1) Mohnike, De Wette, and Erlanger do not specify the time and place.
Letters from the year 1544. no. 3115. 3116. 3117.
No. 3116 .