Can anyone help here?

My grandmother really wants to find out who said/wrote this, and while it isn't directly bookish, I don't know where else to pick literary brains without entering some scary forum.

"For I in thy heart/ Had dwelling/ And thou has in mine/ Forever."

I've searched the Internet in vain. All I found were records of gravestones with this written on them, and nobody seems to be particularly concerned with methods of proper literary documentation on gravestones!

Any clues?