It's a famous book called , a translation of _Guía de Pecadores_ (or "The Sinner's Guide") by Jesuit mission in Japan.
It reads:
> (voicing marks unused)
> _Guia do Pecador - Book 2_ (title in Medieval Portuguese)
What makes it hard to read is _hentaigana_ , now obsolete historic alternate kana, used in the line as:
> **** ****
> _or_
> **** **** (hentaigana in original kanji forms)
* * *
**EDIT** :
~~The shape of the eighth letter, which I read , seems rather peculiar, that more resembles hentaigana or (both for ). There's a possibility that it's a typesetting error (note that the border between kana and cursive style kanji is fuzzy), or meant to be hentaigana for .~~
Sorry, of course it was :)