Reference for Bava Kamma 157:11

הא תנא ליה רישא תנא גנב שגנב מבית הבעלים ותנא גנב שגנב מבית שומר

HE WOULD BE LIABLE.<span class="x" onmousemove="('comment',' For as soon as the animal came into the possession of the thief the theft became complete. ');">¹⁰</span>

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