This is a prayer uttered by someone who I presume is imitating archaic speech:
遍く邪悪より御身を守らん
What is the conjugation used in 守らん? It's doesn't seem like a negative which was my first thought.
守らむ(守らん) consists of the imperfective form (未然形) of 守る + the auxiliary verb む(ん); meaning #2 in 助動詞 む. I think it's the archaic form of 守ろう.
