The usual tune I've heard is one of the many versions of Villikens and his Dinah. However, the whole thing may have grown out of one that starts off:

The old clerk of this parish I know him right well,
He often do toll the eight o'clock bell,
He went to the ale house to take a small sup
And forgot the old church for to lock-a-lock lock...

A mare and a foal ran in at great speed,
The mare from the bible began for to read,
"Oh stay," said the foal, "before you begin,
Whatever you pray for I'll answer amen...

"Let us pray for the millers that grind us our corn,
For they are the greatest rogues that ever were born,
For every bushel they'll take two for toll,
May the devil take the millers," "Amen" said the foal...

etc.

Banjo