You can generate txs files (needed by OpBible) from Sword sources.

You need to have libsword-dev package installed in your computer because
sword sources are binary files able to be read only by specific software.

You can download a "module" (i.e. Bible text in given language+variant) from
https://www.crosswire.org/sword/modules/ModDisp.jsp?modType=Bibles

Unzip the downloaded file in a working directory: the directory with 
a module name is crated. If you do in working directory:

   installmgr -l

the downloaded modules are listed.

   mod2tex module > module.out

a single text file with all Bible text fro given module is created in module.out

   maketxs.py module.out

66 txs files are created and single books.tex file too.