It was narrated that Hakam said:

“I heard Ibn Abi Laila say: ‘Ka’b bin ‘Ujrah met me and said: “Shall I not give you a gift? The Messenger of Allah (ﷺ) came out to us and we said: ‘We know what it means to send greetings on you, but what does it mean to send peace and blessings upon you?’ He said: ‘Say: Allahumma salli ‘ala Muhammadin wa ‘ala ali Muhammadin, kama sallayta ‘ala Ibrahima, innaka Hamidun Majid; Allahumma barik ‘ala Muhammadin wa ‘ala ali Muhammadin, kama barakta ‘ala Ibrahima, innaka Hamidun Majid (O Allah, send your grace, honour and mercy upon Muhammad and upon the family of Muhammad, as You sent Your grace, honour and mercy upon Ibrahim, You are indeed Praiseworthy, Most Glorious. O Allah, send Your blessings upon Muhammad and the family of Muhammad, as You sent Your blessings upon Ibrahim, You are indeed Praiseworthy, Most Glorious).’”

حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا شُعْبَةُ، ح وَحَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ مَهْدِيٍّ، وَمُحَمَّدُ بْنُ جَعْفَرٍ، قَالاَ حَدَّثَنَا شُعْبَةُ، عَنِ الْحَكَمِ، قَالَ سَمِعْتُ ابْنَ أَبِي لَيْلَى، قَالَ لَقِيَنِي كَعْبُ بْنُ عُجْرَةَ فَقَالَ أَلاَ أُهْدِي لَكَ هَدِيَّةً خَرَجَ عَلَيْنَا رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ فَقُلْنَا قَدْ عَرَفْنَا السَّلاَمَ عَلَيْكَ فَكَيْفَ الصَّلاَةُ عَلَيْكَ قَالَ ‏

‏ قُولُوا اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ كَمَا صَلَّيْتَ عَلَى، إِبْرَاهِيمَ إِنَّكَ حَمِيدٌ مَجِيدٌ. اللَّهُمَّ بَارِكْ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ كَمَا بَارَكْتَ عَلَى إِبْرَاهِيمَ، إِنَّكَ حَمِيدٌ مَجِيدٌ ‏

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