A man walked into a public eating house and sat down to eat. Before sitting, he neglected to perform netilat yadayim, the ritual washing of the hands that observant Jews perform before a meal with bread. The omission was small, but the consequences, as the Exempla preserves them, were not.
The innkeeper watched him. He noted that the man did not pause to wash, and drew the obvious inference: this man cannot be a Jew. Everyone in the town knew that Jews washed before eating. If this customer did not wash, he must be a Gentile. The innkeeper went into the back and prepared a dish accordingly. He served the man pork.
The man ate. He did not know what was on his plate. He had walked into a Jewish eating house and assumed that everything served there would naturally be kosher. His failure to perform a small visible custom had silently reclassified him in the eyes of the host.
The Book of Exempla tells the story in a single sentence and lets the irony sit where it falls. The point of netilat yadayim has never been hygiene alone. It is one of the public markers that a Jewish meal is a Jewish meal. When you skip the marker, you are not merely skipping a ritual. You are removing one of the signs by which your own community recognizes you. The man in the story was served pork in a Jewish house because he had stopped looking Jewish at the table. Small rituals carry more weight than they appear to carry.