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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
tabarani:3084 – Bishr b. Mūsá > al-Ḥumaydī > Sufyān > Hishām b. ʿUrwah from his father > Ḥakīm b. Ḥizām

[Machine] He heard Hakim ibn Hizam say, "I said, 'O Messenger of Allah, I have emancipated forty slaves in the pre-Islamic period.' The Prophet ﷺ said, 'You have embraced Islam for what good you have done before.'  

الطبراني:٣٠٨٤ – حَدَّثَنَا بِشْرُ بْنُ مُوسَى ثنا الْحُمَيْدِيُّ ثنا سُفْيَانُ ثنا هِشَامُ بْنُ عُرْوَةَ عَنْ أَبِيهِ

أَنَّهُ سَمِعَ حَكِيمَ بْنَ حِزَامٍ يَقُولُ قُلْتُ يَا رَسُولَ اللهِ إِنِّي أَعْتَقْتُ فِي الْجَاهِلِيَّةِ أَرْبَعِينَ مُحَرَّرًا فَقَالَ النَّبِيُّ ﷺ «أَسْلَمْتَ عَلَى مَا سَبَقَ لَكَ مِنَ الْخَيْرِ»  

See similar narrations below:

Collected by Ṭabarānī
tabarani:3076 – Muḥammad b. ʿAbdullāh al-Ḥaḍramī > Yaḥyá al-Ḥimmānī > Sufyān b. ʿUyaynah > Hishām b. ʿUrwah > Ḥakīm b. Ḥizām

[Machine] I said, "O Messenger of Allah, indeed I have freed forty slaves in the pre-Islamic era." He said, "You have embraced Islam for what preceded it."  

الطبراني:٣٠٧٦ – حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللهِ الْحَضْرَمِيُّ ثنا يَحْيَى الْحِمَّانِيُّ ثنا سُفْيَانُ بْنُ عُيَيْنَةَ عَنْ هِشَامِ بْنِ عُرْوَةَ عَنْ حَكِيمِ بْنِ حِزَامٍ قَالَ

قُلْتُ يَا رَسُولَ اللهِ إِنِّي أَعْتَقْتُ أَرْبَعِينَ مُحَرَّرًا فِي الْجَاهِلِيَّةِ قَالَ «أَسْلَمْتَ عَلَى مَا سَبَقَ لَكَ»