Musnad Ahmad 511
Al-Ahnaf said:
We set out for Hajj, and passed by Madinah. Whilst we were in our camp, someone came to us and said: The people are in a panic in the mosque. My companion and I set out, and we found some people gathered around a group in the mosque. I pushed through them until I got to (that group), where I found ` Ali bin Abi Talib, Az-Zubair, Talhah and Sa`d bin Abi Waqqas. Soon ‘Uthman came walking and said: Is `Ali here? They said: Yes. He said: ls Az-Zubair here? They said: Yes. He said: ls Talhah here? They said: Yes. He said: ls Sa`d here? They said: Yes. He said: I adjure you by Allah, beside Whom there is no other god, do you know that the Messenger of Allah (ﷺ)  said: “Whoever buys the date-drying place of (the tribe of) Banu so- and-so, Allah will forgive him.” so I bought it and went to the Messenger of Allah (ﷺ) and said: I have bought it; he said: `Add it to our mosque and the reward for that will be yours”? They said: Yes. He said: I adjure you by Allah, beside Whom there is no other god, do you know that the Messenger of Allah (ﷺ) said: “Who will buy the well of Roomah?` so I bought it for such and such and went to the Messenger of Allah (ﷺ)  and said: I have bought it - meaning the well of Roomah, and he said: `Make it a water source for the Muslims and the reward for that will be yours`? They said: Yes. He said: I adjure you by Allah, beside Whom there is no other god, do you know that the Messenger of Allah (ﷺ)  looked at the faces of the people on the day of the army of hardship (Tabook) and said: “Whoever equips these men, Allah will forgive him,” so I equipped them until they were not without even reins or ropes? They said: By Allah, yes. He said: O Allah, bear witness, O Allah, bear witness; O Allah, bear witness. Then he left
حَدَّثَنَا بَهْزٌ، حَدَّثَنَا أَبُو عَوَانَةَ، حَدَّثَنَا حُصَيْنٌ، عَنْ عَمْرِو بْنِ جَاوَانَ، قَالَ قَالَ الْأَحْنَفُ انْطَلَقْنَا حُجَّاجًا فَمَرَرْنَا بِالْمَدِينَةِ فَبَيْنَمَا نَحْنُ فِي مَنْزِلِنَا إِذْ جَاءَنَا آتٍ فَقَالَ النَّاسُ مِنْ فَزَعٍ فِي الْمَسْجِدِ فَانْطَلَقْتُ أَنَا وَصَاحِبِي فَإِذَا النَّاسُ مُجْتَمِعُونَ عَلَى نَفَرٍ فِي الْمَسْجِدِ قَالَ فَتَخَلَّلْتُهُمْ حَتَّى قُمْتُ عَلَيْهِمْ فَإِذَا عَلِيُّ بْنُ أَبِي طَالِبٍ وَالزُّبَيْرُ وَطَلْحَةُ وَسَعْدُ بْنُ أَبِي وَقَّاصٍ قَالَ فَلَمْ يَكُنْ ذَلِكَ بِأَسْرَعَ مِنْ أَنْ جَاءَ عُثْمَانُ يَمْشِي فَقَالَ أَهَاهُنَا عَلِيٌّ قَالُوا نَعَمْ قَالَ أَهَاهُنَا الزُّبَيْرُ قَالُوا نَعَمْ قَالَ أَهَاهُنَا طَلْحَةُ قَالُوا نَعَمْ قَالَ أَهَاهُنَا سَعْدٌ قَالُوا نَعَمْ قَالَ أَنْشُدُكُمْ بِاللَّهِ الَّذِي لَا إِلَهَ إِلَّا هُوَ أَتَعْلَمُونَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ مَنْ يَبْتَاعُ مِرْبَدَ بَنِي فُلَانٍ غَفَرَ اللَّهُ لَهُ فَابْتَعْتُهُ فَأَتَيْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقُلْتُ إِنِّي قَدْ ابْتَعْتُهُ فَقَالَ اجْعَلْهُ فِي مَسْجِدِنَا وَأَجْرُهُ لَكَ قَالُوا نَعَمْ قَالَ أَنْشُدُكُمْ بِاللَّهِ الَّذِي لَا إِلَهَ إِلَّا هُوَ أَتَعْلَمُونَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ مَنْ يَبْتَاعُ بِئْرَ رُومَةَ فَابْتَعْتُهَا بِكَذَا وَكَذَا فَأَتَيْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقُلْتُ إِنِّي قَدْ ابْتَعْتُهَا يَعْنِي بِئْرَ رُومَةَ فَقَالَ اجْعَلْهَا سِقَايَةً لِلْمُسْلِمِينَ وَأَجْرُهَا لَكَ قَالُوا نَعَمْ قَالَ أَنْشُدُكُمْ بِاللَّهِ الَّذِي لَا إِلَهَ إِلَّا هُوَ أَتَعْلَمُونَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ نَظَرَ فِي وُجُوهِ الْقَوْمِ يَوْمَ جَيْشِ الْعُسْرَةِ فَقَالَ مَنْ يُجَهِّزُ هَؤُلَاءِ غَفَرَ اللَّهُ لَهُ فَجَهَّزْتُهُمْ حَتَّى مَا يَفْقِدُونَ خِطَامًا وَلَا عِقَالًا قَالُوا اللَّهُمَّ نَعَمْ قَالَ اللَّهُمَّ اشْهَدْ اللَّهُمَّ اشْهَدْ اللَّهُمَّ اشْهَدْ ثُمَّ انْصَرَفَ‏.‏