Mishkat al-Masabih
Ibn ‘Umar said that God’s Messenger forbade selling or giving away the right to inheritance from a manumitted slave. (Bukhari and Muslim.)
وَعَنِ ابْنِ عُمَرَ قَالَ: نَهَى رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَن بيع الْوَلَاء وَعَن هِبته
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