"Allah's Messenger taught me some phrases to say during Al-Witr (Allahummahdini fiman hadait, wa a'fini fiman afait, wa tawallani fiman tawallait, wa barik Li fima atait, wa qini sharra ma qadait, fa Innaka taqdi wa la yuqda Alaik, wa innahu la yadhillu man walait, tabarakta Rabbana wa ta'alait.) 'O Allah guide me among those You have guided, pardon me among those You have pardoned, befriend me among those You have befriended, bless me in what You have granted, and save me from the evil that You decreed. Indeed You decree, and none can pass decree, and none can pass decree upon You, indeed he is not humiliated whom You have befriended, blessed are You our Lord and Exalted.'"
Jami` at-Tirmidhi Book 3, Hadith 12
that the Messenger of Allah (ﷺ) came out to Ubayy bin Ka'b, and the Messenger of Allah (ﷺ) said: "O Ubayy!" And he was performing Salat, so Ubayy turned around but he did not respond to him, so Ubayy finished his Salat quickly. Then he turned to the Messenger of Allah (ﷺ) and said: 'As-Salamu 'Alaikum, O Messenger of Allah!' The Messenger of Allah (ﷺ) said: 'Wa 'Alaikum As-Salam - what prevented you from responding to me when I called you Ubayy?' He said: 'O Messenger of Allah! I was performing Salat.' So he said: 'Do you not find among what Allah revealed to me: Respond to Allah and to the Messenger when they call you to what gives you life?' He said: 'Of course, I shall not repeat that, if Allah wills.' He said: 'Would you like for me to teach you a Surah the likes of which has neither been revealed in the Tawrah, nor the Injil, nor the Zabur, nor in the entire Quran?' He said: "Yes, O Messenger of Allah!' The Messenger of Allah (ﷺ) said: 'What do you recite in your Salat?' He said: 'I recite Umm Al-Quran.' So the Messenger of Allah (ﷺ) said: 'By the One in Whose Hand is my soul! The like of it has neither been revealed in the Tawrah, nor the Injil nor the Zabur, nor in the Furqan. It is the seven oft-repeated, and the Magnificent Quran which I was given.'"
Jami` at-Tirmidhi Book 45, Hadith 1