I must not think of thee; and, tired but strong,
  I shun the thought that lurks in all delight --
  The thought of thee -- or in the blue heaven's height,
or in the fairest passage of a song.
Oh, just beyond the thought thoughts that throng
  This breast, the thought of thee waits hidden yet bright;
  But it must never, never come in sight;
I must stop short of thee the whole day long.
But when sleep comes to close each difficult day,
  When night gives pause to the long watch I keep,
And all my bonds I needs must loose apart,
Must doff my will as raiment laid away, --
  With the first dream that comes with the first sleep
I run, I run, I am gather'd to thy heart.