Reference for Avodah Zarah 83:10

אמר אביי שפחסה וכי פחסה מאי הוי והא תנן פחסה אע"פ שלא חסרה בטלה

Abaye said: [The Mishnah refers to a case] where he only defaced the idol. But if he only defaced it, so what? Have we not taught: If he defaced it, although he did not cause it to be missing anything, it is still annulled!

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