أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا هُشَيْمٌ، عَنْ مَنْصُورِ بْنِ زَاذَانَ، عَنِ ابْنِ سِيرِينَ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم خَرَجَ مِنْ مَكَّةَ إِلَى الْمَدِينَةِ لاَ يَخَافُ إِلاَّ رَبَّ الْعَالَمِينَ يُصَلِّي رَكْعَتَيْنِ ‏.‏

It was narrated from Ibn 'Abbas that: The Messenger of Allah (PBUH) set out from Makkah to Al-Madinah, fearing nothing but the Lord of the worlds, and praying two rak'ahs. Translation Not Available

Book Ref: Sunan An Nisai Book 15 Hadith 1435
Web Ref:  Sunan An Nisai Vol 2 Book 15 Hadith 1436