Ketubot 106 - Influence of the judge
A certain man brought a basket of cheap small fish to Rav Anan, a righteous man. Rav Anan, who was a judge, said "I am not taking your fish, and I am disqualified from judging your case." The man said, "Giving a present to a righteous man is like bringing the best sacrifice in the Temple, please accept." Rav Anan, having disqualified himself from the case anyway, accepted the gift. Still, this is what happened.
Rav Anan sent the man to Rav Nachman's court, saying that he, Rav Anan, was disqualified from judging it. Rav Nachman assumed that the reason was because Ran Anan was a relative of the man, and treated the man with honor. On seeing this, the man's opponent was confused in his arguments and lost the case.
As a consequence, the Prophet Elijah, who used to visit Rav Anan every day, stopped coming. Rav Anan fasted and prayed, and Elijah came back, but now he had a scary appearance, and Rav Anan had to study with Elijah while being hidden in a box. The first set of teachings, before the incident, is called "The Great Book of Elijah," whereas the second set, after the incident, is called "The Small Book of Elijah," and the above is the reason.
Art: The Golden Fish by Paul Klee