On the Implications of finding a "calling" in this world.

“Being is not a general concept which canbe separated from things. It is identical with the things thatexist.... Being is posited by essence. What my essence is, is my being.The fish is in the water, but its essence cannot be separated from thisbeing. Even language identifies being and essence. It is only in humanlife that being is divorced from essence — but only in exceptional, unfortunate case— only there is it possible that a person’s essence is not in the placewhere he is, but it is precisely because of this division that hisspirit is not truly in the place where his body actually is. Only whereyour heart is, there you are. But all things — apart from abnormal cases — like to be in the place where they are, and like to be what they are” (p. 47).

A fine panegyric upon the existing state of things! Apart from abnormalcases, a few exceptional cases, you like to work from your seventh year as a door-keeper in a coal-mine, remaining alone in the dark forfourteen hours a day, and because it is your being therefore it is also your essence. The same applies to a piecer at a self-actor.a It is your “essence” to be subservient to a branch of labour. Cf. Das Wesen des Glaubens, p. 11, “unsatisfied hunger” ..."

This from Theses on Feuerbach by Marx and Engels (M&E) sets up real difficulty for all those people trying to find "their true calling" or that one career that is their essence and passion. Could it just be that the idea of the one true job is a decedent of the "idea" of the being as having a "true" or "natural" place among this society.
This is a critique of those people trying to find themselves among the rank and file of the coal-mine door keeper opportunities confronting a human that is not "one" thing but many, a human that is desperately trying to find how to fit into the dictates of capital instead of self-developing.