Reference for Bava Kamma 225:23

וגזל כנעני מי שרי והתניא אמר ר' שמעון דבר זה דרש ר"ע כשבא מזפירין מנין לגזל כנעני שהוא אסור ת"ל (ויקרא כה, מח) אחרי נמכר גאולה תהיה לו

Has it not been taught<span class="x" onmousemove="('comment',' Cf. Sifra on Lev. XXV, 48. ');">³⁶</span> that R. Simeon stated that the following matter was expounded by R. Akiba when he arrived from Zifirin:<span class="x" onmousemove="('comment',' Prob. the headland of Cyprus; Zephyrium (Jast.). [Greatz, Geschichte, IV, p. 135. connects R. Akiba's visit to Zifirin with his extensive travels for the purpose of rousing the Jews against the Roman tyranny.] ');">³⁷</span> 'Whence can we learn that the robbery of a heathen is forbidden? From the significant words: <i>After that he is sold<span class="x" onmousemove="('comment',' I.e., an Israelite to a Canaanite. ');">³⁸</span></i> he may be redeemed again,<span class="x" onmousemove="('comment',' Lev. XXV, 48. ');">³⁹</span>

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