I thought you're Polish too... :O
I am. It was just a joke (not funny and incomprehensible).
Another version of your joke ends with the devil saying to the Pole: "I knew you wouldn't have the guts to jump", so the Pole jumps.
Anyways, the cow in kalosze joke wins the Suchar of the Year award easily. :)
Here's another:
Flick, Karpin and Santos are sitting on a bench in park and crying. God sees them and asks Flick:
G: Why are you crying, my son?
F: Because my team is in a huge crisis these days.
G: Don't worry. The crisis will be over soon and Germany is going to win the World Cup again.
Then God asks Karpin:
G: Why are you crying, my son?
K: There is a war and my team is banned from all competitions.
G: Don't worry, the war will end soon and your team will be able to play international games again.
Then God looks at Santos, says absolutely nothing, sits down next to him and cries.