"The earliest funeral Lutheran sermons whose texts are extant wre preached by Luther at the Saxon Electors Frederick (1525) and John (1532). Luther preached twice at each of the funerals; these four sermons are the oldest printed funeral sermons of the Lutheran church." These sermons were given to expoud doctrine and console the listener.
In 1545 Johann Spangenberg (1484-1550), an influential pastoral theologian and preacher in Nordhausen published 15 of his funerl sermons, the first collection of its kind in the Lutheran churches.
The preaching of funeral sermons spread from cities and towns to the villages.
"Originally intended to each and edify, by 1600 the funeral sermon had become an uneasy mixture of doctrine and moral instruction with lengthy praise of the deceased and his or her family."
Quotes by Craig M. Koslofsy in The Reformation of the Dead: Death and Ritual in Early Modern Germany,. 1450–1700. See book review here: https://acuriouswanderer.wordpress.com/2011/09/13/the-reformation-of-the-dead/
“To Help the Deceased Guild Brother to His Grave”: Guilds, Death and Funeral Arrangements in Late Medieval and Early Modern Norway, ca. 1300–1900 Håkon Haugland. Online pdf
Link to database of German Funeral Sermons: https://www.personalschriften.de/datenbanken/gesa.html
An example of a funeral sermon can be found at this link: Leichenpredikten for Zacharias Theobald
Link to FamilySearch East Prussia Funeral Sermons: https://familysearch.org/ark:/61903/3:1:3QSQ-G93H-VJ45?
Link to FamilySearch catalog entry for book showing abbreviation used in Funeral Sermons and other early documents. In Latin and German. Vol. 35 of Marburg by Lenz. FamilySearch Call No. 943 G26L
https://www.familysearch.org/search/catalog/2019527?availability=Family%20History%20Library
Vinzenz Lübben, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons
Oekonomische Encyklopädie von J. G. Krünitz [see Leichen Predikt https://kruenitz1.uni-trier.de/
Dissertation: Burial Rituals and the Reformations in Early Modern Europe A Comparative Study by Jeanine Curvers at this link: https://studenttheses.uu.nl/server/api/core/bitstreams/798a4efe-255a-4222-a2cc-c92157b448bf/content