Do what we will,
One horror haunts us still,
And down the course where shines the goal
For the swift contest of the soul
A Spectre glides; where'er we set
Our footsteps, there will he be met,
Our guardian demon: grant us grace
To lift the veil that hides his face!

If once we dare
Those eyes beneath his hair,
If once that demon visage see,
His power is spent, he leaves us free;
But if we try to pass him by,
He'll seize our hand and presently
Will lead us to that land of dream
Where lost men grovel and blaspheme.

Francis Burdett Thomas Coutts-Nevill

http://www.poemhunter.com/poem/the-guardian-demon/