Musannaf Ibn Abi Shayba 21:283

Zayd ibn al-Hubab narrated to us, he said: Abd al-Rahman ibn Abi al-Mawwal narrated to me, he said: I heard Muhammad ibn al-Munkadir narrating to Abdullah ibn al-Hasan, from Jabir, he said: The Messenger of Allah (may Allah bless him and grant him peace) used to teach us the *Istikhara* (seeking guidance) just as he used to teach us the *Surah* from the Qur’an. He said: "When one of you intends to undertake a matter, let him pray two units of prayer other than the obligatory ones. Then let him name the matter and say: 'O Allah, I seek guidance from You by Your knowledge, and I seek ability from You by Your power, and I ask You of Your great bounty. For indeed, You are able and I am not able, and You know and I do not know, and You are the Knower of the unseen. O Allah, if this matter is good for me in my religion and the outcome of my affair, then ordain it for me, facilitate it for me, and bless me in it. And if it is evil for me in my religion and the outcome of my affair, then turn it away from me and turn me away from it, and ordain for me the good wherever it may be, then make me content with it.'"