Reference for Bava Batra 233:3

ר' יונתן אומר לבאי הארץ נתחלקה הארץ שנאמר לאלה תחלק הארץ בנחלה אלא מה אני מקיים לשמות מטות אבותם ינחלו משונה נחלה זו מכל נחלות שבעולם שכל נחלות שבעולם חיין יורשין מתים וכאן מתים יורשין חיין

the land shall be divided for an inheritance,<span class="x" onmousemove="('comment',' Ibid. 53. ');">⁶</span> he applied? — Unto these, [means] 'like these',<span class="x" onmousemove="('comment',' Referring to those that were numbered (ibid. 51), who were twenty years of age and upward. ');">⁷</span> excluding the minors.<span class="x" onmousemove="('comment',' Under twenty. Only those who were at least twenty years of age at the Exodus were included in the number of those to whom the land was divided. Any one under twenty, when leaving Egypt, could only take the share of his father in part or in full according to whether he had brothers or not. ');">⁸</span>

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