Maybe xians are new souls of satanists or they were once satanist.Think about that if a satanist become in another life brainwashed and he become a xian and he made a child who is a new soul then the child will get some power from his parent who got some power because once he was satanist.Jews probably have power from human sacrifice and from their victims (xians and muslims) ,from other victims who's energy they stole.They also have some meditations but I don't know too much about that subject.