For the Melave Malka meal (Saturday night meal to escort the Shabbat queen), Rabbi Hillel of Paritch would always eat chicken that had been freshly slaughtered, salted and prepared that night.
One Shabbat, he was a guest in the home of the chief rabbi, Rav Yosef Tumarkin, in Krementzug. There were two shochtim (ritual slaughterers) in town, one from Lithuanian and one from Poland. Rabbi Hillel would only eat the chickens slaughtered by the Polish chasid.
Immediately after Shabbat, the Rebbetzin arranged for a chicken to be prepared. Unfortunately, the Polish shochet had already left for the slaughterhouse, which was located out of town.
The Rebbetzin was in a dilemma. She knew that Rabbi Hillel was known to eat only meat slaughtered by the Polish shochet. On the other hand, she did not want to return home empty-handed. "My husband," she rationalized, "is the local Rav. If he relies on the other shochet, on this one occasion, it will have to do for Rabbi Hillel as well." Quickly, she ordered the chicken form the Lithuanian shochet and soon the table was set for the Melave Malka meal.
When the chicken was served, Rabbi Hillel sniffed it slightly and set his portion aside, without touching it. The Rav realized that something must be amiss with the chicken and quickly turned to his wife. "Was there a halachic question about the chicken's kashrus?" he inquired.
"Not at all," she assured him. Taking her husband aside, she explained what had happened. "Evidently, Rabbi Hillel has his way of knowing that this chicken was not slaughtered by his usual shochet." The Rav then turned to his guest, telling him what had happened and asking him to explain his reluctance to use meat slaughtered by the Lithuanian shochet. "If, in fact, he is not reliable, why then, I should not be eating chickens slaughtered by him either."
"He is a skilled shochet," replied Rabbi Hillel. "However, I once overheard him speaking disrespectfully about a Torah scholar. Therefore, I do not eat from the meat he has slaughtered." The Rav knew the offended scholar. "How can the shochet atone for his folly? The man whom he shamed has since passed away."
"He should gather ten people to accompany him to the cemetery and beg forgiveness at his grave. After this, there will be no further questions about his slaughtering and I too will rely on him."
From From My Father's Shabbos Table by Rabbi Yehudah Chitrick
