Grüner's house in Cheb became a place J. W. Goethe visited frequently. He met Grüner during a routine customs clearance when he arrived in Cheb in 1820. The educated councillor knew his work well and was eager to get to know the poet. He became Goethe's guide and close friend. Goethe sparked his interest in mineralogy and Grüner soon became an avid mineral collector. On multiple occasions the poet himself sent him to collect samples. Grüner was a versatile personality, in addition to collecting natural history, he collected Cheb folklore, which thanks to him has been preserved in descriptions and records and is a valuable source for understanding the history of this specific Czech-German region (Egerland), whose cultural continuity was violently severed in the 20th century.
An incident described in Goethe's diary in 1822 illustrates Grüner's lively approach to things: On the day of the famous council at Komorní hůrka, which was attended by Count Kaspar Sternberk, the Swedish chemist Jacob Berzelius and the botanist Johann Baptist Pohl, the guests were welcomed with a "grand geological breakfast". It was prepared by Grüner and Goethe on the banks of the Ohře River near Cheb. The main course consisted of a petrified oak trunk lifted from the river by Grüner, and on a makeshift table they laid out rocks and minerals that they collected "far and wide". The company then went to a historically significant meeting at the top of the nearby hill Komorní hůrka to resolve the then pressing question of the volcanic origin of basalt.
A plaque with a German inscription was placed on Gruner's house in 1899 on the initiative of the Society for Cheb Ethnography. It reads: Wolfgang Goethe repeatedly stayed in this house as a guest of councillor Sebastian Grüner. The plaque disappeared in the late 1980s during the renovation of the house. It was later discovered damaged and found refuge in the collections of the Cheb Museum. Today, a newly installed plaque informs about the history of the house.
