With warfare never ending, a person can be an angel or a demon. All it takes is a change of heart under 2Masters that grant you powers to heal the world, or to destroy it.
READ RIGHT TO LEFT - Asian way
Yehwehs can not harm their own people with their spirit weapons because the spirit is from the same spirit, Master Yehweh. But there are exceptional situation where Yehwehs get overwhelmed when the level differences are too great from their own team.