The only purpose of darkness can be to emphasize the light. In this sense, darkness is a nurturer. Consider that it is. Consider that darkness is a blessing. Hidden from view, blessing nevertheless it is.

Where can you go from darkness but into the light? In that sense, darkness is a direct path.

From the illusion of darkness comes the reality of light.

It is not that you adjust your eyes to darkness. It is that you see beyond the darkness.

What can sadness be but a temporary illusion? A visitor in your heart only for a while. A sad stranger who wants to make a home for himself with you and doesn't know when to leave. Most assuredly, sadness overstays its welcome.

Of course, sadness must be some comfort to you, or why would you have it?