Reference for Bava Kamma 160:5

אמרי וכיון דאמרת אין בו משום גזל מאי ניהו תו אין בו משום השב אבידה לבעלים אמר רבינא לעורו

does not apply to it, nor that of returning a lost object to its owner.'<span class="x" onmousemove="('comment',' As required in Deut. XXII, 1-3. ');">⁹</span> Since you have stated that it is permissible to kill it, why again state that it is a sin to keep it? — You might perhaps think that though it is permissible to kill it, there is still no sin committed in keeping it; we are therefore told [that this is not so]. I could still ask: Since you have said that the law of robbery<span class="x" onmousemove="('comment',' Lev. XIX. 13. ');">⁸</span>

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