A man struck his son with a sword and killed him. The case was brought before Umar, who said, "Were it not that I heard the Messenger of Allah ﷺ say, 'A father is not to be killed in retaliation for his son,' I would have executed you before you left this place."
حدثنا أسود بن عامر قال أخبرنا جعفر يعني الأحمر عن مطرف عن الحكم
حذف رجل ابنا له بسيف فقتله فرفع إلى عمر فقال لولا أني سمعت رسول الله ﷺ يقول لا يقاد الوالد من ولده لقتلتك قبل أن تبرح
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Its chain is daif because it is disconnected, for Mujahid bin Jabr was born during the caliphate of Umar, so he did not hear from him, and his narration from him is a mursal one. Jafar is Ibn Ziyad the Red. Mutarrif is Ibn Tarif. Hakam is Ibn Utayba. The hadith has other routes as well. See Sunan al-Kubra by Bayhaqi, 8:38-39, and Talkhis Habir, 336.