Just in case you didn't know......
Interjection: "May God blind me!" was once a serious oath, not sworn in anything but earnest. It's shortening was partly to avoid offence and partly for brevity. See also gawd blimey.
Part of a song by Lonnie Donegan:
'Oh, my old man's a dustman,
He wears a dustman's hat,
He wears cor-blimey trousers
And he lives in a council flat...'