Abdurahman ibn Awf (radiyAllaahu 'anhu) reported: I asked Aisha (radiyAllaahu 'anha), mother of the believers, about words which the Messenger of Allah (sallAllaahu 'alayhi wa sallam) used to open his prayer when he would stand at night.

She (radiyAllaahu 'anha) said: When he (sallAllaahu 'alayhi wa sallam) would stand at night, he would open his prayer by saying,

اللَّهُمَّ رَبَّ جَبْرَائِيلَ وَمِيكَائِيلَ وَإِسْرَافِيلَ فَاطِرَ السَّمَاوَاتِ وَالْأَرْضِ عَالِمَ الْغَيْبِ وَالشَّهَادَةِ أَنْتَ تَحْكُمُ بَيْنَ عِبَادِكَ فِيمَا كَانُوا فِيهِ يَخْتَلِفُونَ اهْدِنِي لِمَا اخْتُلِفَ فِيهِ مِنْ الْحَقِّ بِإِذْنِكَ إِنَّكَ تَهْدِي مَنْ تَشَاءُ إِلَى صِرَاطٍ مُسْتَقِيمٍ

“O Allah, Lord of Jibril, Mika'il, and Israfil; Originator of the Heavens and the Earth; Knower of the unseen and the seen; You judge between Your servants concerning that in which they differ. Guide me, by Your leave, in what people differ concerning the truth. Indeed, You guide whom You will to the straight path.”

 
[Sahih Muslim, Book 4, Number 1694]