That is odd. I cannot find an English translation of this book. Unum Necessarium (‘the only thing necessary’) is the last book that Comenius (1592-1670) wrote. He dedicated it to “earl Ruprecht of the Palts on the Rhein”. The way Comenius wrote, my guess is that this Ruprecht was still alive when the book was published, but which Ruprecht we are talking about, I do not know. But, Comenius’ last book lacks translation to English? This Dutch translation is from 1929; this 1983 printing is a second and revised print. The translation was made by R.A.B. Oosterhuis.
Unum Necessarium is but a little book, 155 pages including introductions and notes. Comenius wrote a massive amount of books about a wide range of subjects. The current title is small and simple; of course, when there is just one thing you really need.
Comenius starts with referring to three Greek myths. Daedalus and his labyrinth, Sisyphus and his stone and Tantalus and his punishment. Comenius keeps talking about labyrinths, Sisyphusstones and Tantalus-disappointments throughout the book. So what is this only thing necessary. Comenius uses several discriptions, but all come to the point of “returning to Christ” (p. 125). Man does not need fancy cloths, lots of money, too much to eat, not even a library full of books (Comenius lost three of his libraries though). Set your mind to Christ and you will have all you need.
Indeed, Unum Necessarium is a very pious and Christian book. Comenius adhered a very specific (and endangered) form of Christianity, the “Unity of the Brethern” (or “Moravian Brethern”), a Moravian Protestant current inspired by the ideas of John Huss (1369-1415).
Comenius travelled around, mostly because he (and his brethern) were forced to leave. He spent many years in the Netherlands. This book was published in the city where he died: Amsterdam.
Unum Necessarium is not really a highly inspirational read (to me). Like I said, it is very piously Christian. Comenius proves himself a realistic and simple religious man who -however he acknowledges other faiths- would like to see ‘his religion’ be the Universal Religion it deserves to be.
‘The only thing necessary’ shows the religious life of a ‘minimalistic believer’.
1983 Rozekruis Pers, isbn 9070196972