"‏ إِذَا نُودِيَ لِلصَّلاَةِ أَدْبَرَ الشَّيْطَانُ لَهُ ضُرَاطٌ حَتَّى لاَ يَسْمَعَ التَّأْذِينَ فَإِذَا قُضِيَ التَّأْذِينُ أَقْبَلَ حَتَّى إِذَا ثُوِّبَ بِالصَّلاَةِ أَدْبَرَ حَتَّى إِذَا قُضِيَ التَّثْوِيبُ أَقْبَلَ حَتَّى يَخْطِرَ بَيْنَ الْمَرْءِ وَنَفْسِهِ يَقُولُ لَهُ اذْكُرْ كَذَا وَاذْكُرْ كَذَا لِمَا لَمْ يَكُنْ يَذْكُرُ مِنْ قَبْلُ حَتَّى يَظَلَّ الرَّجُلُ مَا يَدْرِي كَمْ صَلَّى ‏"

The Apostle (ﷺ) said When the call to prayer is made, Satan runs back and breaks wind so as not to hear the call being made, and when the call is finished. he turns round. When Iqama is proclaimed he turns his back, and when it is finished he turns round to distract a man, saying: Re- member such and such; remember such and such, referring to something the man did not have in his mind, with the result that he does not know how much he has prayed.