The Messenger of Allah ﷺ used to teach us the tashahhud the way he taught us a surah from the Quran. He would say, "The blessed greetings, the good prayers belong to Allah. Peace be upon you, Prophet, and the mercy of Allah and His blessings. Peace be upon us and upon the righteous servants of Allah. I bear witness that there is no god but Allah, and I bear witness that Muhammad is the Messenger of Allah."
كان رسول الله ﷺ يعلمنا التشهد كما يعلمنا السورة من القرآن فكان يقول: التحيات المباركات، الصلوات الطيبات الله، السلام عليك أيها النبي ورحمة الله وبركاته، السلام علينا وعلى عباد الله الصالحين، أشهد أن لا إله إلا الله، وأشهد أن محمدا رسول الله.
Muslim narrated it in the Book of Prayer (403) from Qutayba bin Saeed, who said, Layth (that is, Ibn Saad) narrated to us from Abu Zubayr, from Saeed bin Jubayr and from Tawus, from Ibn Abbas, and he related it. He also mentioned another route for it, from Abdul-Rahman bin Humayd, who said, Abu Zubayr narrated to me, from Tawus, from Ibn Abbas, with the same wording, and he related it.Abu Awana said in his Sahih (2024), I heard Muhammad bin Abdullah bin Abdul-Hakam say, I heard Shafii say, "This is the best hadith narrated from the Prophet ﷺ concerning the tashahhud."As for his statement, "the greetings, the blessed things, the prayers, the good things," Nawawi said, "Its intended meaning is 'and the blessed things and the prayers and the good things,' as in the hadith of Ibn Masud and others, but the conjunction 'and' was omitted for brevity, which is permissible and well known in the language. The meaning of the hadith is that the greetings and what follows them are due to Allah alone, and their true reality is not fitting for anyone besides Him." End of quote.As for what Ibn Majah (902), Nasai (1175, 1281), and Hakim (1/266), and from him Bayhaqi (2/141, 142), all narrated through the route of Ayman bin Nabil, who said, Abu Zubayr narrated to us, from Jabir bin Abdullah, who said, "The Messenger of Allah ﷺ used to teach us the tashahhud just as he taught us a surah from the Quran, 'In the name of Allah and by Allah are the greetings...'" this is an error, along with what was added at the beginning of the text.Bayhaqi said, "Ayman bin Nabil alone narrated it in this way, from Abu Zubayr, from Jabir."Abu Isa said, "I asked Bukhari about this hadith, and he said, 'It is an error, and the correct version is what Layth bin Saad narrated, from Abu Zubayr, from Saeed bin Jubayr and Tawus, from Ibn Abbas.'" Tirmidhi mentioned this in Ilal al-Kabir (2/228).Nasai said in the second place (3/43), "We do not know of anyone who corroborated Ayman bin Nabil in this narration. Ayman, in our view, is not problematic, but the hadith is an error."