The Prophet ﷺ said, "Among the signs of the Hour is that people will boast about one another concerning the mosques."
أخبرنا سويد بن نصر قال أنبأنا عبد الله بن المبارك عن حماد بن سلمة عن أيوب عن أبي قلابة
أن النبي ﷺ قال من أشراط الساعة أن يتباهى الناس في المساجد
Abu Dawud transmitted it in the Book of Prayer, chapter on the building of mosques, hadith no. 449, and Ibn Majah in the Book of Mosques, chapter on the construction of mosques, hadith no. 739, both from the hadith of Hammad bin Salama with the same wording. It is also found in Kubra, hadith no. 768, and Ibn Khuzayma graded it sahih, 2/282.