Sahih Muslim 1823 b
It has been reported on the authority of Ibn 'Umar who said:
I entered the apartment of (my sister) Hafsa. She said: Do yoa know that your father is not going to nominate his successor? I said: He won't do that (i. e. he would nominate). She said: He is going to do that. The narrator said: I took an oath that I will talk to him about the matter. I kept quiet until the next morning, still I did not talk to him, and I felt as if I were carryint, a mountain on my right hand. At last I came to him and entered his apartment. (Seeing me) he began to ask me about the condition of the people, and I informed him (about them). Then I said to him: I heard something from the people and took an oath that I will communicate it to you. They presume that you are not going to nominate a successor. If a grazer of camels and sheep that you had appointed comes back to you leaving the cattle, you will (certainly) think that the cattle are lost. To look after the people is more serious and grave. (The dying Caliph) was moved at my words. He bent his head in a thoughtful mood for some time and raised it to me and said: God will doubtlessly protect His religion. If I do not nominate a successor (I have a precedent before me), for the Messenger of Allah (ﷺ) did not nominate his successor. And if I nominate one (I have a precedent), for Abu Bakr did nominate. The narrator (Ibn Umar) said: By God. when he mentioned the Messenger of Allah (ﷺ) and Abu Bakr, I (at once) understood that he would not place anyone at a par with the Messenger of Allah (ﷺ) and would not nominate anyone.
حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، وَابْنُ أَبِي عُمَرَ، وَمُحَمَّدُ بْنُ رَافِعٍ، وَعَبْدُ بْنُ حُمَيْدٍ، وَأَلْفَاظُهُمْ، مُتَقَارِبَةٌ قَالَ إِسْحَاقُ وَعَبْدٌ أَخْبَرَنَا وَقَالَ الآخَرَانِ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، - أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، أَخْبَرَنِي سَالِمٌ، عَنِ ابْنِ عُمَرَ، قَالَ دَخَلْتُ عَلَى حَفْصَةَ فَقَالَتْ أَعَلِمْتَ أَنَّ أَبَاكَ غَيْرُ مُسْتَخْلِفٍ قَالَ قُلْتُ مَا كَانَ لِيَفْعَلَ ‏.‏ قَالَتْ إِنَّهُ فَاعِلٌ ‏.‏ قَالَ فَحَلَفْتُ أَنِّي أُكَلِّمُهُ فِي ذَلِكَ فَسَكَتُّ حَتَّى غَدَوْتُ وَلَمْ أُكَلِّمْهُ - قَالَ - فَكُنْتُ كَأَنَّمَا أَحْمِلُ بِيَمِينِي جَبَلاً حَتَّى رَجَعْتُ فَدَخَلْتُ عَلَيْهِ فَسَأَلَنِي عَنْ حَالِ النَّاسِ وَأَنَا أُخْبِرُهُ - قَالَ - ثُمَّ قُلْتُ لَهُ إِنِّي سَمِعْتُ النَّاسَ يَقُولُونَ مَقَالَةً فَآلَيْتُ أَنْ أَقُولَهَا لَكَ زَعَمُوا أَنَّكَ غَيْرُ مُسْتَخْلِفٍ وَإِنَّهُ لَوْ كَانَ لَكَ رَاعِي إِبِلٍ أَوْ رَاعِي غَنَمٍ ثُمَّ جَاءَكَ وَتَرَكَهَا رَأَيْتَ أَنْ قَدْ ضَيَّعَ فَرِعَايَةُ النَّاسِ أَشَدُّ قَالَ فَوَافَقَهُ قَوْلِي فَوَضَعَ رَأْسَهُ سَاعَةً ثُمَّ رَفَعَهُ إِلَىَّ فَقَالَ إِنَّ اللَّهَ عَزَّ وَجَلَّ يَحْفَظُ دِينَهُ وَإِنِّي لَئِنْ لاَ أَسْتَخْلِفْ فَإِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم لَمْ يَسْتَخْلِفْ وَإِنْ أَسْتَخْلِفْ فَإِنَّ أَبَا بَكْرٍ قَدِ اسْتَخْلَفَ ‏.‏ قَالَ فَوَاللَّهِ مَا هُوَ إِلاَّ أَنْ ذَكَرَ رَسُولَ اللَّهِ صلى الله عليه وسلم وَأَبَا بَكْرٍ فَعَلِمْتُ أَنَّهُ لَمْ يَكُنْ لِيَعْدِلَ بِرَسُولِ اللَّهِ صلى الله عليه وسلم أَحَدًا وَأَنَّهُ غَيْرُ مُسْتَخْلِفٍ ‏.‏