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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bukhari:3003 – Ismāʿīl > Mālik > Zayd b. Aslam from his father > ʿUmar b. al-Khaṭṭāb

I heard ʿUmar bin Al-Khattab saying, "I gave a horse to be ridden in Allah's Cause and the person who got it intended to sell it or neglected it. So, I wanted to buy it as I thought he would sell it cheap. I consulted the Prophet ﷺ who said, "Do not buy it even if for one Dirham, because he who takes back his gift is like a dog swallowing its vomit."  

البخاري:٣٠٠٣ – حَدَّثَنَا إِسْمَاعِيلُ حَدَّثَنِي مَالِكٌ عَنْ زَيْدِ بْنِ أَسْلَمَ عَنْ أَبِيهِ قَالَ سَمِعْتُ عُمَرَ بْنَ الْخَطَّابِ ؓ يَقُولُ حَمَلْتُ عَلَى فَرَسٍ فِي سَبِيلِ اللَّهِ فَابْتَاعَهُ أَوْ فَأَضَاعَهُ الَّذِي كَانَ عِنْدَهُ فَأَرَدْتُ أَنْ أَشْتَرِيَهُ وَظَنَنْتُ

أَنَّهُ بَائِعُهُ بِرُخْصٍ فَسَأَلْتُ النَّبِيَّ ﷺ فَقَالَ لاَ تَشْتَرِهِ وَإِنْ بِدِرْهَمٍ فَإِنَّ الْعَائِدَ فِي هِبَتِهِ كَالْكَلْبِ يَعُودُ فِي قَيْئِهِ  

See similar narrations below:

Collected by Bukhārī, Ibn Ḥibbān
bukhari:2623 – Yaḥyá b. Qazaʿah > Mālik > Zayd b. Aslam from his father > ʿUmar b. al-Khaṭṭāb

I gave a horse in Allah's Cause. The person to whom it was given, did not look after it. I intended to buy it from him, thinking that he would sell it cheap. When I asked the Prophet ﷺ he said, "Don't buy it, even if he gives it to you for one Dirham, as the person who takes back what he has given in charity, is like a dog that swallows back its vomit."  

البخاري:٢٦٢٣ – حَدَّثَنَا يَحْيَى بْنُ قَزَعَةَ حَدَّثَنَا مَالِكٌ عَنْ زَيْدِ بْنِ أَسْلَمَ عَنْ أَبِيهِ سَمِعْتُ عُمَرَ بْنَ الْخَطَّابِ ؓ يَقُولُ حَمَلْتُ عَلَى فَرَسٍ فِي سَبِيلِ اللَّهِ فَأَضَاعَهُ الَّذِي كَانَ عِنْدَهُ فَأَرَدْتُ أَنْ أَشْتَرِيَهُ مِنْهُ وَظَنَنْتُ أَنَّهُ بَائِعُهُ بِرُخْصٍ فَسَأَلْتُ

عَنْ ذَلِكَ النَّبِيَّ ﷺ فَقَالَ لاَ تَشْتَرِهِ وَإِنْ أَعْطَاكَهُ بِدِرْهَمٍ وَاحِدٍ فَإِنَّ الْعَائِدَ فِي صَدَقَتِهِ كَالْكَلْبِ يَعُودُ فِي قَيْئِهِ  

ذِكْرُ الْبَيَانِ بِأَنَّ هَذَا الْفَرَسَ قَدْ ضَاعَ عِنْدَ الَّذِي كَانَ فِي يَدِهِ، فَأَرَادَ عُمَرُ أَنْ يَشْتَرِيَهُ بَعْدَ ذَلِكَ

ibnhibban:5125 – al-Ḥusayn b. Idrīs al-Anṣārī > Aḥmad b. Abū Bakr > Mālik > Zayd b. Aslam from his father > ʿUmar b. al-Khaṭṭāb

I gave a horse in Allah's Cause. The person to whom it was given, did not look after it. I intended to buy it from him, thinking that he would sell it cheap. When I asked the Prophet ﷺ he said, "Don't buy it, even if he gives it to you for one Dirham, as the person who takes back what he has given in charity, is like a dog that swallows back its vomit." (Using translation from Bukhārī 2623)  

ابن حبّان:٥١٢٥ – أَخْبَرَنَا الْحُسَيْنُ بْنُ إِدْرِيسَ الْأَنْصَارِيُّ قَالَ حَدَّثَنَا أَحْمَدُ بْنُ أَبِي بَكْرٍ عَنْ مَالِكٍ عَنْ زَيْدِ بْنِ أَسْلَمَ عَنْ أَبِيهِ أَنَّهُ قَالَ سَمِعْتُ عُمَرَ بْنَ الْخَطَّابِ يَقُولُ حَمَلْتُ عَلَى فَرَسٍ فِي سَبِيلِ اللَّهِ فَأَضَاعَهُ الَّذِي كَانَ عِنْدَهُ فَأَرَدْتُ أَنْ أَبْتَاعَهُ مِنْهُ وَظَنَنْتُ أَنَّهُ بَائِعُهُ بِرُخْصٍ فَسَأَلْتُ

عَنْ ذَلِكَ رَسُولَ اللَّهِ ﷺ فَقَالَ «لَا تَبْتَعْهُ وَإِنْ أَعْطَاكَهُ بِدِرْهَمٍ وَاحِدٍ فَإِنَّ الْعَائِدَ فِي صَدَقَتِهِ كَالْكَلْبِ يَعُودُ فِي قَيْئِهِ»