Painting serious sorrow

Reading the letters of Van Gogh, came across this -

'As molting time -- when they change their feathers -- is for birds, so adversity or misfortune is the difficult time for us human beings. One can stay in it -- in that time of molting -- one can emerge renewed; but anyhow it must not be done in public and it is not at all amusing, therefore the only thing to do is to hide oneself. . . .

...On the other hand, there is the idle man who is idle in spite of himself, who is inwardly consumed by a great longing for action but does nothing, because it is impossible for him to do anything, because he seems to be imprisoned in some cage, because he does not possess what he needs to become productive, because circumstances bring him inevitably to that point. Such a man does not always know what he could do, but instinctively feels, I am good for something, my life has a purpose after all, I know I that could be quite a different man! How can I be useful, of what service can I be? There is something inside of me, what can it be? . . . '

[Letter #133 (to Theo), July, 1880]

...So you see that I am in a rage of work, though for the moment it does not produce very brilliant results. But I hope these thorns will bear their white blossoms in due time, and that this apparently sterile struggle is no other than the labor of childbirth. First the pain, then the joy.

[Letter #136 (to Theo), September 24, 1880]

I want you to understand clearly my conception of art. One must work long and hard to grasp the essence. What I want and aim at is confoundedly difficult, and yet I do not think I aim too high.

I want to do drawings which touch some people...

In either figure or landscape I should wish to express, not sentimental melancholy, but serious sorrow...

This is my ambition, which is, in spite of everything, founded less on anger than on love, more on serenity than on passion. It is true that I am often in the greatest misery, but still there is a calm pure harmony and music inside me. . . .

[Letter #218 (to Theo), July 19-23, 1882]