Soul is there in everyone but it is veiled. To bring the soul in front, ordinarily man requires few births. It’s like a son of a wrestler is not born a wrestler, he has to prepare himself and the body. From birth his body is not ready with strength to fight, just like that the soul has to go through a preparation to come in the front.
Initially soul is asleep, it has no powers. So if we are engrossed in bad habit and bad company the soul becomes inert and so due to our bad habits and ill-wills, one opens the doors to the wrong forces and they enter into oneself and take possession of it.
Affectionately,
Alok Da