Sunan an-Nasa'i, Volume 2, Book 12, Hadith 1172 (DarusSalam) ⓘ
Abdullah said: "The Messenger of Allah taught us the tashahhud just as he taught us a surah from the Quran: "At-tahiyyatu lillahi was-salawatu wat-tayyibat, as-salamu 'alaika ayyuhan-Nabiyyu wa rahmatAllahi wa baraktuhu. As-salamu 'alaina wa 'ala 'ibad illahis-salihin, ashahdu an la illaha ill-Allah wa ashhadu anna Muhammadan 'abduhu wa rasuluhu (Allah compliments, prayers and pure words are due to Allah. Peace be upon you, O Prophet, and the mercy of Allah (SWT) and his blessings. Peace be upon us and upon the righteous slaves of Allah (SWT). I bear witness that none has the right to be worshipped except Allah and I bear witness that Muhammad is His slave and Messenger)."
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا الْفَضْلُ بْنُ دُكَيْنٍ، قَالَ حَدَّثَنَا سَيْفٌ الْمَكِّيُّ، قَالَ سَمِعْتُ مُجَاهِدًا، يَقُولُ حَدَّثَنِي أَبُو مَعْمَرٍ، قَالَ سَمِعْتُ عَبْدَ اللَّهِ، يَقُولُ عَلَّمَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم التَّشَهُّدَ كَمَا يُعَلِّمُنَا السُّورَةَ مِنَ الْقُرْآنِ وَكَفُّهُ بَيْنَ يَدَيْهِ " التَّحِيَّاتُ لِلَّهِ وَالصَّلَوَاتُ وَالطَّيِّبَاتُ السَّلاَمُ عَلَيْكَ أَيُّهَا النَّبِيُّ وَرَحْمَةُ اللَّهِ وَبَرَكَاتُهُ السَّلاَمُ عَلَيْنَا وَعَلَى عِبَادِ اللَّهِ الصَّالِحِينَ أَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَشْهَدُ أَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُولُهُ " .
also referenced under: Hadith 1171 (Reference) & Book 12, Hadith 143 (In-Book)