One of my "someday/maybe" projects now for a long time has been to compile as many Latin versions (original or translated) of hymns used by Lutherans into a volume that could be used on a Sunday morning alongside of Lutheran Service Book. There is no particular reason why one cannot be singing "Arx firma noster Deus est" while everyone else sings "A mighty fortress is our God" or "Ein feste Burg ist unser Gott."
Of course Cantor Christianus does not stand alone. The author's preface credits and lists many other works along the same lines. Petschely claims that writings become clearer and more lucid the more they are expressed in other languages. Therefore where one may not pay as much attention to a vernacular (German) hymn, when rendered into Latin the original is elucidated for the poet and reader. After giving this and many other reasons for the value of his work, he then acknowledges that "some people will undoubtedly think that this way of singing in Latin is a joke, not suitable enough for those who pursue good literature" (4). These are usually the same people, he notes, that cannot appreciate the beauty of Latin, and besides, why should German Lutherans keep their treasure all to themselves when so many could benefit from these hymns who do not know German?
I offer here just one small sample known to us as "Now Thank We all Our God" (LSB 895). Interestingly enough, LSB places this in the "Harvest and Thanksgiving" section while Petschely lists it as a "post sermon hymn."
41.) Nun dancket alle GOtt, mit Herzen etc.
Nunc plausu manuum cordisque celebremus
DEVM, quem magnas res conficere uidemus
Nos qui ab utero et incunabulis
Ornatos maximis uult beneficiis!
2. Diuitiarum Fons nos laeta mente donet,
Et pace tempora Propitius coronet!
Nos sua gratia constanter protegat,
Et malis omnibus tandem eripiat!
3. Sit PATRI gloria perpetuo Rectori,
Eiusque FILIO et SANCTO SOLATORI,
TRIN-VNI NVMINI, cuius essentia
Est, fuit, et erit, in cuncta secula!