"The Messenger of Allah said: 'When one of you enters the mosque, he is in a state of prayer, so long as the prayer keeps him there, and the angels will send prayer upon anyone of you so long as he remains in the place where he prayed, saying: "O Allah, forgive him; O Allah, have mercy on him; O Allah, accept his repentance," so long as he does not commit Hadath nor disturb anyone.'"  

قَالَ رَسُولُ اللَّهِ ﷺ إِنَّ أَحَدَكُمْ إِذَا دَخَلَ الْمَسْجِدَ كَانَ فِي صَلاَةٍ مَا كَانَتِ الصَّلاَةُ تَحْبِسُهُ وَالْمَلاَئِكَةُ يُصَلُّونَ عَلَى أَحَدِكُمْ مَادَامَ فِي مَجْلِسِهِ الَّذِي صَلَّى فِيهِ يَقُولُونَ اللَّهُمَّ اغْفِرْ لَهُ اللَّهُمَّ ارْحَمْهُ اللَّهُمَّ تُبْ عَلَيْهِ مَا لَمْ يُحْدِثْ فِيهِ مَا لَمْ يُؤْذِ فِيهِ  

The Prophet said: "A muslim does not regularly attend the mosques to perform prayer and remember Allah, but Allah feels happy with him just as the family of one who is absent feels happy when he comes back to them."  

عَنِ النَّبِيِّ ﷺ قَالَ مَا تَوَطَّنَ رَجُلٌ مُسْلِمٌ الْمَسَاجِدَ لِلصَّلاَةِ وَالذِّكْرِ إِلاَّ تَبَشْبَشَ اللَّهُ لَهُ كَمَا يَتَبَشْبَشُ أَهْلُ الْغَائِبِ بِغَائِبِهِمْ إِذَا قَدِمَ عَلَيْهِمْ  

"We performed the Maghrib (prayer) with the Messenger of Allah, then those who went back went back, and those who stayed, stayed. Then the Messenger of Allah came back in a hurry, out of breath, with his garment pulled up to his knees, and said: 'Be of good cheer, for your Lord has opened one of the gates of heaven and is boasting of you before the angels, saying: "Look at My slaves; they have fulfilled one obligatory duty and are awaiting another."  

صَلَّيْنَا مَعَ رَسُولِ اللَّهِ ﷺ الْمَغْرِبَ فَرَجَعَ مَنْ رَجَعَ وَعَقَّبَ مَنْ عَقَّبَ فَجَاءَ رَسُولُ اللَّهِ ﷺ مُسْرِعًا قَدْ حَفَزَهُ النَّفَسُ و قَدْ حَسَرَ عَنْ رُكْبَتَيْهِ فَقَالَ أَبْشِرُوا هَذَا رَبُّكُمْ قَدْ فَتَحَ بَابًا مِنْ أَبْوَابِ السَّمَاءِ يُبَاهِي بِكُمُ الْمَلاَئِكَةَ يَقُولُ انْظُرُوا إِلَى عِبَادِي قَدْ قَضَوْا فَرِيضَةً وَهُمْ يَنْتَظِرُونَ أُخْرَى  

The Messenger of Allah said: "If you see a man frequenting the mosques, then bear witness to his faith. Allah says: 'The mosques of Allah shall be maintained only by those who believe in Allah and the Last Day. [At-Taubah: 18]'"  

عَنْ رَسُولِ اللَّهِ ﷺ قَالَ إِذَا رَأَيْتُمُ الرَّجُلَ يَعْتَادُ الْمَسَاجِدَ فَاشْهَدُوا لَهُ بِالإِيمَانِ قَالَ اللَّهُ تَعَالَى {إِنَّمَا يَعْمُرُ مَسَاجِدَ اللَّهِ مَنْ آمَنَ بِاللَّهِ} الآيَةَ