BAYHAQI 16677:
from ʿUmar And Ylak Wamā Qātil al-Thalāthah —
[Machine] Abu Abdullah Al-Hafiz informed us that Abu Abdullah Al-Sana'ani narrated from Ishaq ibn Ibrahim, who narrated from Abdul Razzaq, who narrated from Ma'mar, who narrated from Al-Zuhri, who narrated from Abu Bakr ibn Abdur Rahman ibn Al-Harith ibn Hisham, who narrated from his father, who said: I heard a bishop from the people of Najran speaking to Umar ibn Al-Khattab saying, "O Amir al-Mu'minin, beware of the killer of the three!" Umar said, "Woe to you! Who is the killer of the three?" The man said, "He is the person who comes to the Imam with lies, and the Imam is then killed because of the words of this liar. Thus, he has killed himself, his companion, and his Imam."
البيهقي ١٦٦٧٧:
عن عمر و يلك وما قاتل الثلاثه —
أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ أَنْبَأَ أَبُو عَبْدِ اللهِ الصَّنْعَانِيُّ ثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ أَنْبَأَ عَبْدُ الرَّزَّاقِ عَنْ مَعْمَرٍ عَنِ الزُّهْرِيِّ عَنْ أَبِي بَكْرِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ الْحَارِثِ بْنِ هِشَامٍ عَنْ أَبِيهِ قَالَ سَمِعْتُ أَسْقُفًّا مِنْ أَهْلِ نَجْرَانَ يُكَلِّمُ عُمَرَ بْنَ الْخَطَّابِ ؓ يَقُولُ يَا أَمِيرَ الْمُؤْمِنِينَ احْذَرْ قَاتِلَ الثَّلَاثَةِ قَالَ عُمَرُ وَيْلَكَ وَمَا قَاتِلُ الثَّلَاثَةِ؟ قَالَ الرَّجُلُ يَأْتِي الْإِمَامَ بِالْكَذِبِ فَيَقْتُلُ الْإِمَامُ ذَلِكَ الرَّجُلَ بِحَدِيثِ هَذَا الْكَذَّابِ فَيَكُونُ قَدْ قَتَلَ نَفْسَهُ وَصَاحِبَهُ وَإِمَامَهُ
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