Write long and hard enough, and at some certain distant point, your writing will take hold of you, almost as if by force.
It's as if all the years and days and hours of hard work sum up to the recitation of an incantation of sorts, which if you are lucky will one day float up off the pages and possess you, come over you, take ownership of you, dragging you miraculously along.
But it takes ages, and most folks give up long before the transformation can find root. For the first 10 years or so, you write your work. For the next 50, your work writes you. Take ownership of your writing long enough and it will happen, eventually. And when it does, it’ll be exciting and mystical and somehow even liberating.
The work will still be work — how can it ever be anything else? — but it will cease to be labor or toil so much as something near to divine mandate. You no longer do it because you should but because, somehow, you must. Because it's the thing you were born for and to.
And that is when the magic really begins.