A Little Help from the Masters
In the event that you sit down to write your vows and draw a complete blank, you can always turn to the great poets and lyricists who have gone before. This is a commonly used idea, and it works very nicely.
One caution, though: Before you use anyone else's words to express your devotion to your fiancé, make sure they're appropriate. Some poems whose titles sound like love poems spiral downward into a story of obsession or other unhealthy emotions; song lyrics can also be misleading. And try to avoid using an entire
It's one thing, for example, to work the opening lines of a beautiful love song into your vows; it's another to stand on the altar and read the entire thing, especially if it runs about twenty verses. That could be interpreted as a lack of planning on your part, as though you didn't care enough to punch up the vows with your own heartfelt words. So choose to use someone else's words wisely, but also use them (relatively) sparingly.
Some of the all-time best romantic poetry comes from:
George Gordon, Lord Byron
Edna St. Vincent Millay
John Keats
Emily Dickinson
Elizabeth Barrett Browning
Dante Gabriel Rossetti
William Shakespeare
Of course, there are countless others, but if you have very little experience with poetry, researching the works of these poets is a good starting point. And remember, you can also look for words of wisdom in modern-day poetry and song lyrics; just don't try to pass the words off as your own (you can count on someone calling you out on it).

