It was narrated from Ibn 'Abbas that a man spoke to the Prophet about something and the Prophet said:"Innal-hamda lillahi nahmaduhu wa nasta'inahu, man yahdih Illahu fala mudilla lahu wa man yudlil Illahu fala hadiya lahu, wa ashhadu an la ilaha illallahu (wahdahu lasharika lahu) wa ashhadu anna Muhammadan 'abdahu wa rasuluhu. Amma ba'd (Praise be to Allah, we seek His help. Whomsoever Allah guides will never be led astray, and whomsoever Allah leaves astray, no one can guide. I bear witness that there is none worthy of worship but Allah (alone with no partners) and I bear witness that Muhammad is His slave and Messenger. To proceed)."
أَخْبَرَنَا عَمْرُو بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ عِيسَى، قَالَ حَدَّثَنَا يَحْيَى بْنُ زَكَرِيَّا بْنِ أَبِي زَائِدَةَ، عَنْ دَاوُدَ، عَنْ عَمْرِو بْنِ سَعِيدٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ رَجُلاً، كَلَّمَ النَّبِيَّ صلى الله عليه وسلم فِي شَىْءٍ فَقَالَ النَّبِيُّ صلى الله عليه وسلم " إِنَّ الْحَمْدَ لِلَّهِ نَحْمَدُهُ وَنَسْتَعِينُهُ مَنْ يَهْدِهِ اللَّهُ فَلاَ مُضِلَّ لَهُ وَمَنْ يُضْلِلِ اللَّهُ فَلاَ هَادِيَ لَهُ وَأَشْهَدُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَحْدَهُ لاَ شَرِيكَ لَهُ وَأَشْهَدُ أَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُولُهُ أَمَّا بَعْدُ " .
Nesai
The Book of Marriage • Hadith 3278