Sahih Muslim Book - 6, Hadith - 1801

وَحَدَّثَنِى هَارُونُ بْنُ عَبْدِ اللَّهِ وَمُحَمَّدُ بْنُ رَافِعٍ قَالاَ حَدَّثَنَا وَهْبُ بْنُ جَرِيرٍ أَخْبَرَنِى أَبِى قَالَ سَمِعْتُ قَيْسَ بْنَ سَعْدٍ يُحَدِّثُ عَنْ عَطَاءٍ عَنِ ابْنِ عَبَّاسٍ قَالَ بَعَثَنِى الْعَبَّاسُ إِلَى النَّبِىِّ -صلى الله عليه وسلم- وَهُوَ فِى بَيْتِ خَالَتِى مَيْمُونَةَ فَبِتُّ مَعَهُ تِلْكَ اللَّيْلَةَ فَقَامَ يُصَلِّى مِنَ اللَّيْلِ فَقُمْتُ عَنْ يَسَارِهِ فَتَنَاوَلَنِى مِنْ خَلْفِ ظَهْرِهِ فَجَعَلَنِى عَلَى يَمِينِهِ.

It was narrated that Ibn 'Abbas said: "Al-'Abbas sent me to the Prophet (s.a.w) when he was in the house of my maternal aunt Maimunah, and I stayed with him that night. He got up and prayed at night, and I stood on his left, but he made me move behind his back and put me on his right."