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nasai-kubra:6991 – Qutaybah b. Saʿīd > Ḥammād > ʿAmr > Ṭāwus

"The Messenger of Allah ruled that a slave (should be given as Diyah) for a fetus." Tawus said: "A horse would do in place of a slave." (Using translation from Nasāʾī 4816)  

الكبرى للنسائي:٦٩٩١ – أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ قَالَ حَدَّثَنَا حَمَّادٌ عَنْ عَمْرٍو عَنْ طَاوُسٍ أَنَّ عُمَرَ اسْتَشَارَ النَّاسَ فِي الْجَنِينِ فَقَالَ

حَمَلُ بْنُ مَالِكً «قَضَى رَسُولُ اللهِ ﷺ فِي الْجَنِينِ غُرَّةً» قَالَ طَاوُسٌ الْفَرَسُ غُرَّةٌ  

See similar narrations below:

Collected by Nasāʾī, Bayhaqī
nasai:4816 – Qutaybah > Ḥammād > ʿAmr > Ṭāwus

"The Messenger of Allah ruled that a slave (should be given as Diyah) for a fetus." Tawus said: "A horse would do in place of a slave."  

النسائي:٤٨١٦ – أَخْبَرَنَا قُتَيْبَةُ قَالَ حَدَّثَنَا حَمَّادٌ عَنْ عَمْرٍو عَنْ طَاوُسٍ أَنَّ عُمَرَ اسْتَشَارَ النَّاسَ فِي الْجَنِينِ فَقَالَ

حَمَلُ بْنُ مَالِكٍ قَضَى رَسُولُ اللَّهِ ﷺ فِي الْجَنِينِ غُرَّةً قَالَ طَاوُسٌ إِنَّ الْفَرَسَ غُرَّةٌ  

bayhaqi:16418 – al-Ḥasan b. Muḥammad b. Isḥāq > Yūsuf b. Yaʿqūb > Sulaymān b. Ḥarb > Ḥammād b. Zayd > ʿAmr b. Dīnār > Ṭāwus > ʿUmar b. al-Khaṭṭāb Saʾal al-Nās > al-Janīn Fadhakar al-Ḥadīth

[Machine] The Messenger of Allah ﷺ decided about the fetus and Tawus al-Faris said, "It is a fetus."  

البيهقي:١٦٤١٨ – أَخْبَرْنَاهُ أَبُو الْحَسَنِ عَلِيُّ بْنُ مُحَمَّدٍ الْمُقْرِئُ أنبأ الْحَسَنُ بْنُ مُحَمَّدِ بْنِ إِسْحَاقَ ثنا يُوسُفُ بْنُ يَعْقُوبَ ثنا سُلَيْمَانُ بْنُ حَرْبٍ ثنا حَمَّادُ بْنُ زَيْدٍ عَنْ عَمْرِو بْنِ دِينَارٍ عَنْ طَاوُسٍ أَنَّ عُمَرَ بْنَ الْخَطَّابِ ؓ سَأَلَ النَّاسَ عَنِ الْجَنِينِ فَذَكَرَ الْحَدِيثَ قَالَ

فَقَضَى رَسُولُ اللهِ ﷺ فِي الْجَنِينِ غُرَّةً وَقَالَ طَاوُسٌ الْفَرَسُ غُرَّةٌ