Reference for Shevuot 44:2

איפוך אחד זה ואחד זה לא מעל לפי שאין מעילה בקונמות דברי רבי מאיר וחכמים אומרים הוא מעל וחבירו לא מעל

Raba said: - [If a man says,] T swear shall not eat,' and he ate dust, he is exempt. Raba inquired: [If a man says.] I SWEAR I shall not eat dust,' what amount [must he eat to make him liable]? [Shall we say:] Since he said, I shall not eat,' his intention was a kazayith, or, since it is not something that people eat, [his intention was] a minute quantity? - Let it stand. <br>

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