Johannes Mathesius was a Protestant preacher in Jáchymov. He made a name for himself preaching for miners, and his sermons included findings about mining, quarrying, minerals and the technologies used to process them. His German-languages writings became one of the foundations of what would later become the montane sciences. He also established the local Latin library and amassed a valuable collection of minerals.

Johannes Mathesius, together with Georgius Agricola, was a distinguished renaissance figure associated not only with Jáchymov, but also with the history of world science. The glory days of Jáchymov date back to the establishment of the mining town by the counts of Šlik in 1516. The town saw its biggest boom prior to 1546, when the Habsburg King Ferdinand I stripped the Šliks of their powers and the town became royal property. Johannes Mathesius first worked here as the rector of the Latin school in 1532. Under his guidance the school achieved a high standard and Mathesius set up the famed Latin library to cater to its needs. He wanted to complete his theological studies under Martin Luther in Wittenberg, where he had formerly lived, but had been unable to finish for financial reasons. In Jáchymov he succeeded in raising the money he needed to study and for several years, as he himself writes in Luther’s biography, became his “companion at the desk”. He was not only Luther’s pupil, but also a close friend and later his biographer. In 1541 a delegation of Jáchymov burghers asked him to take up the position of preacher in the Church of St. Joachim and St. Anna. At that time Jáchymov was an island of Protestantism in the Šlik estate. Mathesius accepted the post and after having been ordained (appointed as preacher) by Luther himself, became the preacher of Jáchymov in the following year. He remained in Jáchymov until his death, and so witnessed the town at the height of its glory and its later decline.

His work that is now considered valuable for the montane sciences is Sarepta oder Bergpostil (the mining postil) – a set of German-language sermons with a mining theme. In it, Mathesius provides testimony to “quarrying here in the Jáchymov spiritual mine”; theological passages are accompanied by often highly detailed interpretations and descriptions of mining equipment, mining technologies and the differences between minerals and how they were used, which was very similar to Agricola’s famous Twelve Books on Mining and Metallurgy.

What is crucial to him, however, despite his extensive interpretation of new mining knowledge, which comes across as a kind of “evening school for miners”, is still the Creator of Ore, the Heavens and the Earth: “I am a spiritual miner and will remain one, if it is God’s will that I live and serve the supreme Lord above, Jesus Christ.”

Mathesius was inspired not only by Agricola’s work; he actively sought to further his knowledge and took a keen interest in everything that was new relating to mines. He also amassed an extensive collection of minerals. He did not come across Agricola himself while he was working in Jáchymov, but they later met and exchanged friendly correspondence together. This relationship was somewhat cool initially, as Agricola was a Catholic and during the religious conflicts of the Schmalkaldic War, which also extended into Bohemia’s western borders, matters of religion were a sore point. However, the two scholars overcame this barrier and both benefited from their friendship.

Connected places:
Memorial plaque of Johannes Mathesius on the Evangelical Church in Jáchymov

Exposition of the Latin School Library in JáchymovPomník Georgia Agricoly v Jáchymově; Pamětní deska Johanna Mathesia na evangelickém kostele v Jáchymově; Muzeum Královská mincovna Jáchymov; Pamětní tabulka na domě Johanna Mathesia v Jáchymově; Knihovna latinské školy v Jáchymově

Keywords: history of natural sciences; geology; mineralogy; Lutheranism; the Šliks; ore mining; montane sciences; Sarepta or mining postil