A Fair Trade
The Divrei Chaim of Sanz was once conducting a siyum to celebrate finishing all of Shas when he found himself stuck on the meaning of a particular Tosfos. He traveled to the author of Be’er Moshe, the Rebbe of Kozhnitz, and asked for his help in understanding the difficult Tosfos.
In his great humility, Rav Moshe claimed that he did not understand it either. “You have already concluded all of Shas,” he said, “whereas I have just finished saying all of Sefer Tehillim.”
The Sanzer Rav was not put off. “Perhaps you would agree to an exchange?” he said. “I will trade you my learning and my siyum on all of Shas for your siyum on Sefer Tehillim.”
“No,” said the Be’er Moshe, shaking his head, “I will not trade.” In the end he agreed to help, and the two sat down to learn the Tosfos together. Halfway through, thanks to the Kozhnitzer, the Sanzer Rav understood.