“The same fact that Boccaccio offers in support of religion might be adduced in behalf of a republic: "It exists in spite of its ministers." ”

Say what ??

I suppose what he is trying to say is that despite the hypocrisy of its ministers, the true republic does still exist.

Heine lived in a very unstable time in Germany, the Weavers revolt of 1844, the rebellious tone of a cruel leadership over the working class. Though he did not embrace Marx's proletariat industrialization, he was progressive in his thinking about change because of the ruling class. The same thing can be said of the birth of the Progressive party around 1900 or so in America due to the same hardships faced in the USA.
In spite of growing up as a jew to catholic then to Protestant. Simply put as Archer states. But never the less he sided against Plato.

Natural law ultimately supersedes carnal man's tyranny. Inalienable rights exist, even in the most enslaved and down-trodden. No matter the administration of theocratic despots, the noble being will eventually seek liberty.