Sunan an-Nasa'i, Volume 2, Book 13, Hadith 1265 (DarusSalam) ⓘ

It was narrated from Wa'il bin Hujr that : He saw the Prophet sitting during the prayer. He lay his left foot on the ground and placed his forearms on his thighs, and pointed with his forefinger, supplicating with it.

أَخْبَرَنَا مُحَمَّدُ بْنُ عَلِيِّ بْنِ مَيْمُونٍ الرَّقِّيُّ، قَالَ حَدَّثَنَا مُحَمَّدٌ، - وَهُوَ ابْنُ يُوسُفَ الْفِرْيَابِيُّ - قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَاصِمِ بْنِ كُلَيْبٍ، عَنْ أَبِيهِ، عَنْ وَائِلِ بْنِ حُجْرٍ، أَنَّهُ رَأَى النَّبِيَّ صلى الله عليه وسلم جَلَسَ فِي الصَّلاَةِ فَافْتَرَشَ رِجْلَهُ الْيُسْرَى وَوَضَعَ ذِرَاعَيْهِ عَلَى فَخِذَيْهِ وَأَشَارَ بِالسَّبَّابَةِ يَدْعُو بِهَا ‏.‏