Sunan an-Nasa'i, Volume 4, Book 34, Hadith 3754 (DarusSalam)

It was narrated that Zaid bin Thabit said: The Messenger of Allah said: "Whoever gives a life-long gift, it belongs to the one to whom he gave it, both during his life and after his death. And do not give things on the basis of Ruqba, for whoever is given something on the basis of Ruqba, it becomes part of his estate."

أَخْبَرَنَا مُحَمَّدُ بْنُ عُبَيْدِ اللَّهِ بْنِ يَزِيدَ بْنِ إِبْرَاهِيمَ، قَالَ أَخْبَرَنِي أَبِي أَنَّهُ، عَرَضَ عَلَىَّ مَعْقِلٌ عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ حُجْرٍ الْمَدَرِيِّ، عَنْ زَيْدِ بْنِ ثَابِتٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنْ أَعْمَرَ شَيْئًا فَهُوَ لِمُعْمَرِهِ مَحْيَاهُ وَمَمَاتَهُ وَلاَ تَرْقُبُوا فَمَنْ أَرْقَبَ شَيْئًا فَهُوَ لِسَبِيلِهِ ‏" ‏ ‏.‏

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