Muwatta Malik, Book 2, Hadith 29 (USC-MSA)

Yahya related to me from Malik from al-Ala ibn Abd ar-Rahman from his father from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, went to the burial grounds and said, "Peace be upon you, home of a people who believe! We shall be among you, Allah willing. I wish that I had seen our brothers!" The people with him said, "Messenger of Allah! Are we not your brothers?" "No," he said, "You are my companions. Our brothers are those who have not yet come. And I will precede them to the Hawd. (The Hawd: the watering place of the Prophet, may Allah bless him and grant him peace, from which he will give to the people of his community on the day of rising.)" They asked him, "Messenger of Allah! How will you recognise those of your community who come after you?" He said, "Doesn't a man who has horses with white legs and white blazes on their foreheads among totally black horses recognise which ones are his own?" They said, "Of course, Messenger of Allah." He went on, "Even so will they come on the day of rising with white marks on their foreheads, hands and feet from wudu, and I will precede them to the Hawd. Some men will be driven away from the Hawd as if they were straying camels and I shall call out to them, 'Will you not come? Will you not come? Will you not come?' and someone will say, 'They changed things after you,' so I shall say, 'Then away with them, away with them, away with them!' "

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ الْعَلاَءِ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم خَرَجَ إِلَى الْمَقْبُرَةِ فَقَالَ ‏"‏ السَّلاَمُ عَلَيْكُمْ دَارَ قَوْمٍ مُؤْمِنِينَ وَإِنَّا إِنْ شَاءَ اللَّهُ بِكُمْ لاَحِقُونَ وَدِدْتُ أَنِّي قَدْ رَأَيْتُ إِخْوَانَنَا ‏"‏ ‏.‏ فَقَالُوا يَا رَسُولَ اللَّهِ أَلَسْنَا بِإِخْوَانِكَ قَالَ ‏"‏ بَلْ أَنْتُمْ أَصْحَابِي وَإِخْوَانُنَا الَّذِينَ لَمْ يَأْتُوا بَعْدُ وَأَنَا فَرَطُهُمْ عَلَى الْحَوْضِ ‏"‏ ‏.‏ فَقَالُوا يَا رَسُولَ اللَّهِ كَيْفَ تَعْرِفُ مَنْ يَأْتِي بَعْدَكَ مِنْ أُمَّتِكَ قَالَ ‏"‏ أَرَأَيْتَ لَوْ كَانَ لِرَجُلٍ خَيْلٌ غُرٌّ مُحَجَّلَةٌ فِي خَيْلٍ دُهْمٍ بُهْمٍ أَلاَ يَعْرِفُ خَيْلَهُ ‏"‏ ‏.‏ قَالُوا بَلَى يَا رَسُولَ اللَّهِ ‏.‏ قَالَ ‏"‏ فَإِنَّهُمْ يَأْتُونَ يَوْمَ الْقِيَامَةِ غُرًّا مُحَجَّلِينَ مِنَ الْوُضُوءِ وَأَنَا فَرَطُهُمْ عَلَى الْحَوْضِ فَلاَ يُذَادَنَّ رِجَالٌ عَنْ حَوْضِي كَمَا يُذَادُ الْبَعِيرُ الضَّالُّ أُنَادِيهِمْ أَلاَ هَلُمَّ أَلاَ هَلُمَّ أَلاَ هَلُمَّ فَيُقَالُ إِنَّهُمْ قَدْ بَدَّلُوا بَعْدَكَ فَأَقُولُ فَسُحْقًا فَسُحْقًا فَسُحْقًا ‏"‏ ‏.‏

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also referenced under: Book 2, Hadith 59 (In-Book)