Calling starts in the nature of the human self.

“True vocation joins self and service, as Fredrick Buchner asserts when he defines vocation as ‘the place where your deep gladness meets the world’s deep need.’ Buchner’s definition starts with the self and moves toward the needs of the world: it begins, wisely, where vocation begins — not in what the world needs (which is everything), but in the nature of the human self, in what brings the self joy, the deep joy of knowing that we are here on earth to be the gifts that God created.”

-Parker Palmer, Let Your Life Speak: Listening for the voice of vocation, p 17