(2) باب الْمُبَاهَاةِ فِي الْمَسَاجِدِ
It was narrated from Anas that the Prophet (ﷺ) said:
"One of the portents of the Hour will be that people will show off in building Masjids."
Reference: Sunan an-Nasa'i 689
In-book reference: Book 8, Hadith 2
English translation: Vol. 1, Book 8, Hadith 690