Woe be to thee, you have broken the neck of your friend, you have broken the neck of your friend-he said this twice. If one of you has to praise his friend at all, he should say: I think (him to be) so and Allah knows it well and I do not know the secret of the heart and Allah knows the destined end, and I cannot testify his purity against Allah but (he appears) to be so and so.  

مَدَحَ رَجُلٌ رَجُلاً عِنْدَ النَّبِيِّ ﷺ قَالَ فَقَالَ وَيْحَكَ قَطَعْتَ عُنُقَ صَاحِبِكَ قَطَعْتَ عُنُقَ صَاحِبِكَ مِرَارًا إِذَا كَانَ أَحَدُكُمْ مَادِحًا صَاحِبَهُ لاَ مَحَالَةَ فَلْيَقُلْ أَحْسِبُ فُلاَنًا وَاللَّهُ حَسِيبُهُ وَلاَ أُزَكِّي عَلَى اللَّهِ أَحَدًا أَحْسِبُهُ إِنْ كَانَ يَعْلَمُ ذَاكَ كَذَا وَكَذَا  

Messenger of Allah, no person is more excellent than he after Messenger of Allah ﷺ. Thereupon Allah's Apostle ﷺ said: Woe be to thee, you have broken the neck of your friend, and he said this twice. Then Messenger of Allah ﷺ said: If anyone has to praise his brother at all, he should say: I think him to be so and so, and even on this he should say: I do not consider anyone purer than Allah (considers).  

عَنِ النَّبِيِّ ﷺ أَنَّهُ ذُكِرَ عِنْدَهُ رَجُلٌ فَقَالَ رَجُلٌ يَا رَسُولَ اللَّهِ مَا مِنْ رَجُلٍ بَعْدَ رَسُولِ اللَّهِ ﷺ أَفْضَلُ مِنْهُ فِي كَذَا وَكَذَا فَقَالَ النَّبِيُّ ﷺ وَيْحَكَ قَطَعْتَ عُنُقَ صَاحِبِكَ مِرَارًا يَقُولُ ذَلِكَ ثُمَّ قَالَ رَسُولُ اللَّهِ ﷺ إِنْ كَانَ أَحَدُكُمْ مَادِحًا أَخَاهُ لاَ مَحَالَةَ فَلْيَقُلْ أَحْسِبُ فُلاَنًا إِنْ كَانَ يُرَى أَنَّهُ كَذَلِكَ وَلاَ أُزَكِّي عَلَى اللَّهِ أَحَدًا  

his hadith has been transmitted on the authority of Shu'ba with a slight variation of wording.  

رَجُلٌ مَا مِنْ رَجُلٍ بَعْدَ رَسُولِ اللَّهِ ﷺ أَفْضَلُ مِنْهُ  

You killed him, or you sliced the back of a person.  

سَمِعَ النَّبِيُّ ﷺ رَجُلاً يُثْنِي عَلَى رَجُلٍ وَيُطْرِيهِ فِي الْمِدْحَةِ فَقَالَ لَقَدْ أَهْلَكْتُمْ أَوْ قَطَعْتُمْ ظَهْرَ الرَّجُلِ  

Messenger of Allah ﷺ commanded us that we should throw dust upon the faces of those who shower too much praise.  

قَامَ رَجُلٌ يُثْنِي عَلَى أَمِيرٍ مِنَ الأُمَرَاءِ فَجَعَلَ الْمِقْدَادُ يَحْثِي عَلَيْهِ التُّرَابَ وَقَالَ أَمَرَنَا رَسُولُ اللَّهِ ﷺ أَنْ نَحْثِيَ فِي وُجُوهِ الْمَدَّاحِينَ التُّرَابَ  

What is the matter with you? And he said: Verily, Messenger of Allah ﷺ said: When you see those who shower (undue) praise (upon others), throw dust upon their faces.  

أَنَّ رَجُلاً جَعَلَ يَمْدَحُ عُثْمَانَ فَعَمِدَ الْمِقْدَادُ فَجَثَا عَلَى رُكْبَتَيْهِ وَكَانَ رَجُلاً ضَخْمًا فَجَعَلَ يَحْثُو فِي وَجْهِهِ الْحَصْبَاءَ فَقَالَ لَهُ عُثْمَانُ مَا شَأْنُكَ فَقَالَ إِنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا رَأَيْتُمُ الْمَدَّاحِينَ فَاحْثُوا فِي وُجُوهِهِمُ التُّرَابَ  

This hadith has been narrated on the authority of Miqdad through another chain of transmitters.  

عَنِ النَّبِيِّ ﷺ بِمِثْلِهِ