Meanings of tub-thumper in English

There was something of the tub-thumper about every one of them.

For the genius of a tub-thumper is that he is usually born deaf.

He had expelled Bernardo da Feltre, another tub-thumper whom he suspected of political subversion, but he treated Savonarola with indulgence.

Shakespeare's "universal sympathy"-toquote Coleridge-didnot include the plainly-clad tub-thumper who dared to accuse him to his face of serving the Babylonish Whore.

I often wonder what born tub-thumpers are like in their own homes.

"Always a-preaching, the old tub-thumper," I heard William say to himself; but he made no further reference to the subject.