like someone said a saint said, its okay to reject an angel out
of caution. better safe than sorry. The only excuse for those
non human or inhuman voices would be, that the demons
were once this kind of being, and in faking it might sound like
the real thing, so this might be the real thing, but frankly, i
doubt it. Why would they sing like this when they knew they
could be heard, when normally they sometimes seem human
until you know otherwise? Better safe than sorry. Several
people got an almost instinctive gut level rejection attitude
going, "it gave me the willies" and similar comments. Trust
no one and nothing. Even Christ can be imitated by demons.
there was a monk who was tricked into worshipping a demon
who pretended to be Christ, and later became possessed,
until his friends dragged him physically into church and threw
him to the ground at the foot of the altar or in front of the
iconostasis I forget which. Apparently he was freed then.