As one who, reading late into the night,
When overcome by sleep, turns off the light
And yields whatever he can sense by sight

To what the gates of ivory or of horn
Will send him, sightless as a child unborn,
To goad, amuse, remind, reveal or warn,

So may I turn a light off and embrace
With resignation, better still with grace,
The dreamless sleep that all awake must face.

David Berman

http://www.poemhunter.com/poem/grace-37/