Robert Crawford - On Marriage.

Whom Love has joined no man may put asunder,
And he has never joined those who can part:
Marriage is this, no more, howe'er priests moan;
The rest is words, mere words, and custom's vapour
The heart will brush aside as easily
As fancy paints a picture.

Robert Crawford

http://www.poemhunter.com/poem/on-marriage-4/