"If there are no dogs in Heaven, then when I die I want to go where they went."   -- Will Rogers

"We give dogs time we can spare, space we can spare and love we can spare.  And in return, dogs give us their all. It's the best deal man has ever made."  -- M. Facklam

"The reason a dog has so many friends is that he wags his tail instead of his tongue."  --  Anonymous

"A dog teaches a boy fidelity, perseverance, and to turn around three times before lying down."  -- Robert Benchley

"I wonder if other dogs think poodles are members of a weird religious cult."  -- Rita Rudner

"There is no psychiatrist in the world like a puppy licking your face."  -- Ben Williams

"A dog is the only thing on earth that loves you more than he loves himself."  -- Josh Billings

"The average dog is a nicer person than the average person." -- Andrew A. Rooney

"Ever consider what they must think of us? I mean, here we come back from a grocery store with the most amazing haul -- chicken, pork, half a cow. They must think we are the greatest hunters on earth!" -- Anne Tyler

"If I have any beliefs about immortality, it is that certain dogs I have known will go to heaven, and very, very few persons."  -- James Thurber

"Women and cats will do as they please, and men and dogs should relax and get used to the idea."  -- Robert Heinlin

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if you have to put a pet down (or just love dogs), I highly recommend:
  Dog Years by the poet Mark Doty: http://www.markdoty.org/

I think the way he put it was something like:
Part of your stewardship of a dog through his life is to help the dog leave this life appropriately (with grace).

from the book:
"One of the unspoken truths of American life is how deeply people grieve over the animals who live and die with them, how real that emptiness is, how profound the silence is these creatures leave in their wake."