Love's but to be had this way:
Reverent you must be with her,
Letting your heart night and day
Dreamy in her beauty stir.
God has set her to a tune
You may never match until,
Like the moonlight in the moon,
You with her own passion fill.
Is she worth this to you, worth
All that you can think or say —
The one flower of life on earth?
If not, put your dream away!
Close the portals of your speech,
Let not e'en a fancy stir,
If your rapture can but reach
To her beauty — not to her.

Robert Crawford

http://www.poemhunter.com/poem/song-3-5/