There are some difficulties with translating this, but it is not impossible. "Living dead" is an oxymoron and I'm not sure if Latin has an equivalent phrase, but it does have several words for "ghost". "Amen" is a Hebrew word but my dictionary says it came into Late Latin. I don't know anybody who is well versed in anything but Classical Latin and neither am I, but here is my offer:
Pro Deo (serviendo) exsulabuntur relicti spiritus impiorum e mortuis peragrantibus ad damnationem aeternam.
in the name of god impure souls of the living dead shall be banished into eternal damnation. amen
Which translates more strictly to:
"On behalf of (serving) God, the remnant spirits of the impious shall be banished from the wandering dead to eternal damnation."
I took a little bit of license with it, but I think it's going to get nasty if you try to translate that English directly into Latin. Add the "amen" if you like
flebile nescio quid queritur lyra, flebile lingua murmurat exanimis, respondent flebile ripae