Those are my principles, and if you don't like them... well, I have others.
The basic plot of the film is that Rhino takes the part of Rufus T. Moneybags, the chairman of the German Bishops' Conference. He has become extremely rich as a result of a dodgy "church tax", and wishes to declare independence from the Catholic Church, citing the precedent of the great Martin Z. Luther. This will enable the German church to become even richer, and make up its own rules, such as rejecting all the traddy Christian teaching about marriage and the family.
In the words of Rhino: "Please accept my resignation. I don’t care to belong to any church that will have me as a member."
"There ain't no Sanity Clause for cardinals." Rhino with "Chico" Baldisseri.
Naturally, the repressive Roman Church, led by businessman Francis I. Pope, is opposed to the Moneybags "Go it alone" policy, but at the Synod Francis is told in no uncertain terms: "From the moment I picked up the Catechism until I put it down I was convulsed with laughter. Some day I intend reading it."
Time for reflection: Rhino and "Harpo" Kasper, the one with nothing useful to say.
Eccles verdict: the characters played by Marx, Baldisseri and Kasper are as ludicrous as any we have ever seen, but the plot is totally implausible. Watch out for veteran comic Tina Beattie in the "Margaret Dumont" role of the foolish old woman.