Anas reported God’s Messenger as saying, "Stand close together in your rows, bring them near one another, and stand neck to neck, for by Him in whose hand my soul is, I see the devil coming in through openings in the row like a number of small black sheep.” Abu Dawud transmitted it.

وَعَنْ أَنَسٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «رُصُّوا صُفُوفَكُمْ وَقَارِبُوا بَيْنَهَا وَحَاذُوا بِالْأَعْنَاقِ فَوَالَّذِي نَفْسِي بِيَدِهِ إِنِّي لَأَرَى الشَّيْطَانَ يَدْخُلُ مِنْ خَلَلِ الصَّفِّ كَأَنَّهَا الْحَذَفُ» . رَوَاهُ أَبُو دَاوُد