Hadith 17:963
Shababa ibn Sawwar narrated to us, he said: Shu'bah narrated to us, from Khalid al-Hadhdha', from 'Abd al-Rahman ibn Abi Bakrah, from his father, who said: A man praised another man in the presence of the Messenger of Allah, may Allah bless him and grant him peace. The Prophet, may Allah bless him and grant him peace, said to him: "Woe to you! You have cut the neck of your companion," [repeating it] several times. Then he said: "If one of you must praise his brother, let him say: 'I reckon him [to be such and such],' and I do not purify anyone before Allah."
حدثنا شبابة بن سوار قال حدثنا شعبة عن خالد الحذاء عن عبد الرحمن بن أبي بكرة عن أبيه قال مدح رجل رجلا عند رسول الله صلى الله عليه وسلم فقال له النبي صلى الله عليه وسلم ويحك قطعت عنق صاحبك مرارا ثم قال إن كان مادحا أخاه لا محالة فليقل له أحسبه ولا ازكي على الله أحدا