Commentary for Bava Kamma 52:3
אמר רבה היתה אבן מונחת לו בחיקו ולא הכיר בה ועמד ונפלה לענין נזקין חייב לענין ארבעה דברים פטור לענין שבת מלאכת מחשבת אסרה תורה לענין גלות פטור
concerning Sabbath<span class="x" onmousemove="('comment',' I.e., if while unaware of the stone in his bosom he carried it with him into the open public thoroughfare, thus violating the Sabbath; cf. Shab. 96b. ');"><sup>8</sup></span> [there will similarly be exemption] as it is [only] work that has been [deliberately] purposed that is forbidden by the Law;<span class="x" onmousemove="('comment',' V. infra 60a; Hag. 10b. ');"><sup>9</sup></span> in a case of manslaughter<span class="x" onmousemove="('comment',' I.e., if, when the stone fell down, it killed a human being; v. Num. XXXV. 9-34. ');"><sup>10</sup></span> there is exemption from fleeing [to a city of refuge];<span class="x" onmousemove="('comment',' Since he never had any knowledge of the stone being in his bosom, he could in no way be made responsible criminally for the accidental manslaughter. ');"><sup>11</sup></span>