TABARANI 13245:
from ʿUbaydullāh b. ʿAbdullāh b. ʿUmar from his father —
[Machine] That Umar ibn Al-Khattab gave charity to a man with a horse in the path of Allah, then he found Umar selling it. So he came to the Messenger of Allah ﷺ and said, "O Messenger of Allah, I gave charity to so-and-so with a horse, and I found him selling it. Should I buy it?" The Messenger of Allah ﷺ said, "Do not buy it and do not count it as part of your charity."
الطبراني ١٣٢٤٥:
عن عبيد الله بن عبد الله بن عمر عن أبيه —
أَنَّ عُمَرَ بْنَ الْخَطَّابِ تَصَدَّقَ عَلَى رَجُلٍ بِفَرَسٍ فِي سَبِيلِ اللهِ فَوَجَدَهُ عُمَرُ يَبِيعُهَا فَأَتَى إِلَى رَسُولِ اللهِ ﷺ فَقَالَ يَا رَسُولَ اللهِ إِنِّي تَصَدَّقْتُ عَلَى فُلَانٍ بِفَرَسٍ وَإِنِّي وَجَدْتُهُ يَبِيعُهَا أَفَأَشْتَرِيهَا؟ فَقَالَ رَسُولُ اللهِ ﷺ «لَا تَشْتَرِهَا وَلَا تَعُدْ فِي صَدَقَتِكَ»
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