Gittin Daf 34

The Gemara relates a story about R' Yehudah who was trying to get the son-in-law of R' Yirmiyah of Bira to give a Get to his wife. Every time he got him to acquiesce to send a Get, R' Yirmiyah's son-in-law would subsequently nullify the Get causing R' Yehudah to start over again. Finally, R' Yehudah after extracting another Get from the recalcitrant husband, R' Yehudah ordered the messengers to stuff their ears with something so that they would not be able to hear the husband nullify the Get. This teaches us an important lesson. Sometimes there are people who try to undo your efforts to do what's right and the only answer is to stuff our ears and not hear anything. Of course, we also need to know when to take out what's in our ears and listen to what we're told!