Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) said: "When you see a person who is accustomed to coming to the mosque (for attending, praying, and taking care), then bear witness to his faith. Allah Almighty says: «‏‏‏‏إِنَّمَا يَعْمُرُ مَسَاجِدَ اللَّهِ مَنْ آمَنَ بِاللَّهِ وَالْيَوْمِ الْآخِرِ» ‏‏‏‏ [ سورة التوبة: 18 ] 'Indeed, only those maintain the mosques of Allah who believe in Allah and the Last Day.'"