The isnad for this version typically runs: Ahmad ibn Hanbal ← Abd al-Razzaq ← Ma’mar ← Ibn Shihab al-Zuhri ← Sa’id ibn al-Musayyib ← Abu Hurayra. This chain is considered highly robust. Abd al-Razzaq al-San’ani is a trustworthy muhaddith , Ma’mar ibn Rashid is reliable, and Ibn Shihab al-Zuhri is a master of the isnad system. The presence of Sa’id ibn al-Musayyib—a major Successor and jurist—transmitting directly from Abu Hurayra adds further weight. Consequently, most Hadith scholars grade this report as sahih (authentic) or at least hasan (good).
When the companions heard the initial statement—that cursing one’s parents is among the greatest major sins ( Al-Kaba'ir )—they were astonished. In the tribal society of 7th-century Arabia, as in many cultures today, the honor of one's parents was paramount. It seemed inconceivable that a sane person would directly curse their own mother or father, those who gave them life and nurtured them. musnad ahmad 6929