In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Salmaan [radiyallaahu anhu] wrote to Abu Ad-Dardaa [radiyallaahu anhu], saying, “O my brother! It is incumbent upon you to [attach yourself] to the Masjid and stick to it, for indeed I heard the Prophet [sallal laahu alayhi wasallam] saying, ‘The Masjid is the house of every pious person'”.
Shaikh Zaid Bin Haadi [rahimahullaah] said:
Firstly: The hadeeth is proof to show that the most virtuous place on the earth are the Masaajid and the best of the people are its maintainers, because indeed they are people of Eemaan based on the evidence:[ إِنَّمَا يَعۡمُرُ مَسَـٰجِدَ ٱللَّهِ مَنۡ ءَامَنَ بِٱللَّهِ وَٱلۡيَوۡمِ ٱلۡأَخِرِ وَأَقَامَ ٱلصَّلَوٰةَ وَءَاتَى ٱلزَّڪَوٰةَ وَلَمۡ يَخۡشَ إِلَّا ٱللَّهَۖ فَعَسَىٰٓ أُوْلَـٰٓٮِٕكَ أَن يَكُونُواْ مِنَ ٱلۡمُهۡتَدِينَ – The Mosques of Allah shall be maintained only by those who believe in Allah and the Last Day; perform As-Salat (Iqamat-as-Salat), and give Zakat and fear none but Allah. It is they who are expected to be on true guidance. [Surah At-Tawbah. Aayah 18]
Secondly: [The reward for] prayer in the Masjid is multiplied [i.e. 27 times] and none is excused for being absent from the Masaajid [i.e. except one who has a legislated Islamic excuse]. Continuous presence in the Masaajid and attaching one’s heart to them is a sign of one’s Eemaan, strength and desire for good.
[At-taleeqaat Al-Maleehah Alaa Silsilah Al-Ahaadeeth As-Saheehah. Vol 1. Page 286. Slightly paraphrased]