Book 17: The Book of the Prohibited actions

Abu Hurairah (May Allah be pleased with him) said: The Messenger of Allah (ﷺ) said, "If anyone hears a man inquiring in the mosque about something he has lost, he should say: 'La raddaha Allahu 'alaika (May Allah not restore it to you),' for mosques are not built for this purpose."

[Muslim]

Abu Hurairah (May Allah be pleased with him) said: The Messenger of Allah (ﷺ) said, "When you see someone buying or selling in the mosque, say to him: 'La arbaha-Allahu tijarataka (May Allah not make your bargain profitable)!' When you see someone announcing something lost in it, say: 'May Allah not restore it to you!"'

[At-Tirmidhi].

Buraidah (May Allah be pleased with him) said: A man announced (the loss of his camel) in the mosque, uttering these words: "Has any one seen my red camel?" Upon this the Messenger of Allah (ﷺ) said, "May it not be restored to you! The mosques are built for what they are meant to be (i.e., prayer, remembrance of Allah, acquiring knowledge, etc.)."

[Muslim].

'Amr bin Shu'aib on the authority of his grandfather (May Allah be pleased with him) said: The Messenger of Allah (ﷺ) prohibited (us) from buying and selling in the mosque; (he also prohibited us from) making announcement in it about something lost and from reciting poems in it.

[Abu Dawud and At- Tirmidhi].

As-Sa'ib bin Yazid (May Allah be pleased with him) said: While I was in the mosque, someone threw a pebble at me, and when I looked up, I saw that it was 'Umar bin Al-Khattab, who said: "Go and call me these two men." I brought them and 'Umar (May Allah be pleased with him) asked them: "Where are you from?" On their replying that they belonged to At-Taif, he said: "Had you been the inhabitants of Al-Madinah, I would have given you a beating for raising your voices in the mosque of the Messenger of Allah (ﷺ)."

[Al- Bukhari].