Martin Jahn [Janus, Jähn, Jahn, Jan] was a German poet. On March 14, 1644 he was registered at the University of Königsberg - with high probability of already being trained as a musician. Here he studied theology for several semesters, until he received an employment as a musician in Steinau an der Steinau (Upper Silesia). In the course of the counter-reformation he fled to Niederlausitz. He served at the two Protestant Churches in Sorau as director of music, probably with support of the baron Sigismund Seifried von Promnitz. After the death of his sponsor (June 30, 1654), he worked as Rector and Kantor at the city school in Sagen (North Silesia, from which, however, he was driven out again during denomination confusions. After a long period of looking for a new job, he accepted the post of Kantor in Ohlau, where the reformator Herzogin (Duchess) Luise resided.
Of Martin Jahn's works (many are considered as lost) only the church hymn (song) Jesu, meiner Seelen Wonne exists. His Passionale melicum, which includes also texts by Andreas Gryphius, Martin Opitz), offers what is considered as erste umfassende Sammlung ev. Passionslyrik ("the first comprehensive collection of Protestant Passion lyrics").