EXOD257 Rebbi was sitting and expounding, when he smelled the smell of garlic; whereupon he said: "Whoever ate garlic, let him leave." R. Chiyya stood up and he left -- at which they all stood up and left! And where did R. Chiyya learn this [i.e., that this was the proper response (though he himself had not eaten the garlic)]? From: "Till when will you [i.e., all of the Jews] refuse ..." [The blame is being relegated to all of the Jews to save individual offenders from embarrassment] (Sanhedrin 11a]