عَنِ ابْنِ عُمَرَ رَضِيَ اللَّهُ عَنْهُ قَالَ: اعْتَكَفَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فِي الْعَشْرِ الْأَوَاخِرِ مِنْ رَمَضَانَ فَاتُّخِذَ لَهُ بَيْتٌ مِنْ سَعَفٍ، قَالَ: فَأَخْرَجَ رَأْسَهُ ذَاتَ يَوْمٍ، فَقَالَ: ((إِنَّ الْمُصَلِّيَ يُنَاجِي رَبَّهُ، فَلْيَنْظُرْ أَحَدُكُمْ بِمَا يُنَاجِي رَبَّهُ، وَلَا يَجْهَرْ بَعْضُكُمْ عَلَى بَعْضٍ بِالْقِرَاءَةِ))
Narrated by Sayyiduna Abdullah bin Umar (may Allah be pleased with him): The Messenger of Allah (peace and blessings be upon him) performed i'tikaf in the last ten days of Ramadan, so a chamber made of palm branches was constructed for him. One day, the Prophet (peace and blessings be upon him) put his head out from the chamber and said: Indeed, the one who is praying is conversing with his Lord, so each of you should consider how he converses with his Lord, and no person should recite aloud over another.