Carroll, Franklin and Chase, with orders from the Continental Congress, invited the Canadians to become the 14th colony which would have included complete freedom of religion. However, the Canadians rejected the invitation.
This invitation gave the other founders further reasons to regard freedom of religion and the lengths to which it should go.
Freedom of religion was put into the free market meaning that there would be absolutely no strictures on any religion - any church could rise or fall on its own merit.
Thanks for that little bit of additional history about Canada.