look at this sentence:

... hoping for reunification with protestant and the jews' conversion.

does that mean: with protestants' conversion and jews" conversion? or just: jews' conversion and protestant?

and another question: why he didn't write (protestants)?

Question

look at this sentence:

... hoping for reunification with protestant and the jews' conversion.

does that mean: with protestants' conversion and jews" conversion? or just: jews' conversion and protestant?

and another question: why he didn't write (protestants)?

Answer

There must be a word missing after protestant. If it’s referring to a church it should be Protestant. You can’t have ‘reunification’ with ‘conversion’.

Answer

I'd assume it means hoping for two things: 1. reunification with protestant and 2. the jews' conversion.
It would be easier to say with more information though. This fragment is a bit short. As for why 'protestant' and not 'protestants', really impossible to beat without being able to read the wider passage. Maybe a typo?