From 1548, Johannes Rhenanus studied theology in Marburg, in 1553 he was ordained by Adam Krafft, the reformer of Hessen.
In 1566, he married Catharina Brown († 1586), daughter of the rent writer Jost Braun von Melsungen.
In 1559, he appointed him as the Salzgreben and entrusted him against the resistance of Pfännerschaft, with the supervision of the important timber industry.
However, the Landgraf admonished Rhenanus and his co-author and Co-Salzgreben Christoph Homberg not to give up the work in favour of debauchery.
He could use higher flame temperatures by putting the boiling pans, which so far, hung over an open fire, on a grill of bricks.
In 1575, William IV allowed him to drive a tunnel in the Hoher Meissner hillside of Schwalbental, to explore further the coal deposits on.
Rhenanus also worked on improving the Ross Art (The technique by which brine was pumped from the earth) Since 1560.
He recognized the shortcomings of the Goepel plant, a conveyor system, which was driven by two horses and developed its pumping station, which for centuries was in use in other places as well.
By replacing fossil fuels by renewable energyRhenanus anticipated an element of the industrial revolution.
In 1584, his ruler allowed him a several months long trip to Pomerania, where he was to investigate a new salt vein.
He visited numerous salt mines, iron ore huts and gravel works and also wrote a travel description, which is preserved to the very day.
Rhenanus' son Martin was a doctor of medicine and practiced as such in the neighbouring town of Eschwege.
His homonymous grandson, John Rhenanus, following his grandfather's footsteps was also an alchemist and the physician to the Landgraf Moritz the Scholar.
In Bad Sooden-Allendorf, there is not only a Rhenanus-school, but also a Rhenanusplatz and Rhenanushaus (Municipal House of the Protestant parish of St. Mary).
For the annual Brunnenfest, Rhenanus is embodied by a pastor in traditional costumes of his time, presented, next to the mayor, who represents the Landgraf.