Rabbi Levi Yitzchak of Berditchev (1740–1809) spent his life acting as the self-appointed character witness for the Jewish people, engaging in a constant dialogue with G‑d, pointing out the unique qualities of every Jew he met. The following is one of the best-known “Berditchever” stories:
It was the afternoon before Passover, and Rabbi Levi Yitzchak was wandering through the streets of the Jewish quarter seeking out local smugglers. From one he quietly asked for a quote on contraband tobacco, from another he inquired about the availability of smuggled brocades and embroideries. No matter the merchandise he sought, everything was available for the right price.
However, when he started asking his newfound acquaintances to supply him with some bread or whiskey, those very same businessmen who had previously proved so accommodating balked. “Rabbi,” said one, “are you trying to insult me? The Seder will be starting in just a few hours, and no Jew would have even a speck of chametz left in his home or business.”
No matter the price offered, not one merchant was willing or able to come up with even a crumb of bread or a dram of alcohol. The town had converted into a chametz-free zone.
Thrilled with the results of his failed quest, the rabbi looked up to heaven and declared: “G‑d Almighty, look down with pride at Your people! The czar has border guards and tax commissioners dedicated to his commands. The police and the courts are devoted to tracking down and punishing smugglers and black marketeers, and yet anything one could possibly want is available. Contrast this with the faith and fidelity of Your Jews. It has been over 3,000 years since you commanded us to observe Passover. No police, no guards, no courts and jails enforce this edict—and yet every Jew keeps Your laws to the utmost!
“Mi k’amcha Yisrael—Who is like Your nation, Israel?!”



Is there a Mokoir for this story?
I heard it with the following manner:
Reb Levik was close with the local leader and would answer all questions for him raised against the Jews.
One day the question came up; are the Jews really loyal to Hashem?
Reb Levik said he would answer on condition the king wouldn't punish anyone.
Reb Levik gathered all the Jews of the city to the Shul and brought the king with him and asked them to go home and bring back any linen they had (there was a ban on owning linen in that city.) People looked at each other, left and came back with linen hidden under their clothes. Good he said, now bring any Chometz you owne (it was Erev Pesach). All the Jews started to question aloud, 'bit it's Erev Pesach, we don't have any Chometz." Reb Levik was pleased and said they can leave.
He then turned to the king and asked "now do you see!?"