There was once a Jewish innkeeper who, when Jewish guests came to him, gave them kasher meat, but when a non-Jew sat at his table, he gave him swine's flesh to eat.

Once upon a time a Jew came in whom he did not know as a Jew, sat down at the table without washing his hands, and said to the host: "Give me a good piece of meat."

Thinking he was a non-Jew, since he had not washed his hands, the host brought him a piece of pork. The Jew did not notice it, but thought it was a good piece of beef and ate it.

After he had eaten his meal, he turned to the innkeeper and said: "Mr. Innkeeper, how much do I owe you?"

The innkeeper said: "You owe me so and so much."

The guest thought that the price was too high, and said to the host: "Do you charge so much for a piece of beef?"

The host replied: "Swine's flesh is very expensive,"

Then the guest said: "But I am a Jew, why did you give me pork to eat?"

Then the host said: "Why did you not wash your hands? Jews always wash their hands before eating, non-Jews do not. Therefore I took you for a non-Jew."

So it happened that he was given swine's flesh to eat. Therefore one should always wash one's hands before and after meals.