BUKHARI 128:
from Anas b. Mālik —
"Once Muʿadh was along with Messenger of Allah ﷺ as a companion rider. Messenger of Allah ﷺ said, "O Muʿadh bin Jabal." Muʿadh replied, "Labbaik and Saʿdaik. O Messenger of Allah ﷺ!" Again the Prophet ﷺ said, "O Muʿadh!" Muʿadh said thrice, "Labbaik and Saʿdaik, O Messenger of Allah ﷺ!" Messenger of Allah ﷺ said, "There is none who testifies sincerely that none has the right to be worshipped but Allah and Muhammad is his Apostle, except that Allah, will save him from the Hell-fire." Muʿadh said, "O Messenger of Allah ﷺ ! Should I not inform the people about it so that they may have glad tidings?" He replied, "When the people hear about it, they will solely depend on it." Then Muʿadh narrated the above-mentioned Hadith just before his death, being afraid of committing sin (by not telling the knowledge).
البخاري ١٢٨:
عن انس بن مالك —
أَنَّ النَّبِيَّ ﷺ وَمُعَاذٌ رَدِيفُهُ عَلَى الرَّحْلِ قَالَ يَا مُعَاذُ بْنَ جَبَلٍ قَالَ لَبَّيْكَ يَا رَسُولَ اللَّهِ وَسَعْدَيْكَ قَالَ يَا مُعَاذُ قَالَ لَبَّيْكَ يَا رَسُولَ اللَّهِ وَسَعْدَيْكَ ثَلاَثًا قَالَ مَا مِنْ أَحَدٍ يَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَنَّ مُحَمَّدًا رَسُولُ اللَّهِ صِدْقًا مِنْ قَلْبِهِ إِلاَّ حَرَّمَهُ اللَّهُ عَلَى النَّارِ قَالَ يَا رَسُولَ اللَّهِ أَفَلاَ أُخْبِرُ بِهِ النَّاسَ فَيَسْتَبْشِرُوا قَالَ إِذًا يَتَّكِلُوا وَأَخْبَرَ بِهَا مُعَاذٌ عِنْدَ مَوْتِهِ تَأَثُّمًا
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