Whale decoration on Catholic pulpits in Poland and Czechia and the story of Jonah
A Pulpit in the Form of a Whale in the Eighteenth-Century Polish Church of Saints Peter and Paul in Duszniki-Zdrój.
Such a decoration for a pulpit is highly unusual in Catholic churches, and is found chiefly in Poland and Bohemia. The image of the whale evidently alludes to the Old Testament Book of Jonah. Jonah, who had disobeyed the Lord, was swallowed by a great fish. After three days in the belly of the fish, Jonah was cast up on dry land and set off, with astonishing success, to proclaim God's message in Nineveh.
The Christological reading of the parable of Jonah links his three days in the belly of the fish with the three days the Lord spent in the tomb. Jonah, emerging unharmed from the fish's maw, thus appears, as it were, in the guise of the Risen Christ.
In short, for a priest to stand by the whale's jaws during a sermon is the same as to strike a prophetic pose.

