Hadith 109

Bulugh al-Maram

Book 2: The Book of Prayer
وَعَنْ أَبِي ذَرٍّ ‏- رضى الله عنه ‏- 1‏ قَالَ : قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ إِذَا قَامَ أَحَدُكُمْ فِي اَلصَّلَاةِ فَلَا يَمْسَحِ اَلْحَصَى , فَإِنَّ اَلرَّحْمَةَ تُوَاجِهُهُ } رَوَاهُ اَلْخَمْسَةُ بِإِسْنَادٍ صَحِيحٍ 2‏
Abu Dhar (RA):

Allah's Messenger (ﷺ) said: "When one of you is praying he must not remove pebbles (from his face) for the mercy is facing him." [Reported by al-Khamsah with a Sahih (authentic) chain].