This document is not by Luther. It is found in the St. Louis edition, vol. XVI, no. 1212, Col. 1863 f. See the introduction there. We would have the same here if Burkhardt, p. 214, did not find a reference to it with the heading: "Luthers Antwort an den päbstlichen Legaten" 2c. with the note: "Orig. von Luthers Hand. Printed Altenb. Ausg. VI, 123 (cf. Seckendorf III, 42) without date." The Altenburg edition has 1. e. the heading: "Preface of D. Martin Luther on the advertisement of the emperor and pope to the protesting estates full because of a Christian Concilii", and also Seckendorf says that to the things (in illa, that is to the documents, which concern the advertisement, which are partly included in the St. Louis edition, Vol. XVI, No. 1212 to No. 1216) a very modest preface was put by Luther. In fact, however, this preface was written for the printing of the documents (but not by Luther), as it indicates itself, thus after the completion of the whole trade, which found its conclusion on June 30 through the joint response of the protesting estates to the advertisement.
No. 1989.