The prohibition of making lost property announcements in the masjid
Abu Huraira, may Allah be pleased with him, reported:
The Messenger of Allah (may the peace and blessings of Allah be upon him) said: If anyone hears a man crying out in the mosque about something he has lost, he should say: May Allah not restore it to you, for the mosques were not built for this.
[Muslim]
The mosques were built to establish the rituals of Islam: praying, remembering Allah, reciting the Qur'an, and teaching the religious and linguistic sciences in addition to the other sciences that benefit people in their religious and worldly affairs.
Glorifying the mosques is a type of glorifying the rituals, which is a sign of piety, and a proof that the heart is free from what disturbs the faith and what contradicts the light of certainty.
Allah willed to elevate these houses over everything that is incompatible with the sacredness and the function of the best places on the earth.
Among these ettiquets, which the Muslim should observe in the mosque is not to make lost property announcements in the masjid, because the mosques were not built for this purpose.
What is meant in this hadeeth is the camel, and the other animals.
It is prohibited to ask in the mosque about one`s camel, or cow, or donkey. The attendees shall respond to him saying: “May Allah not restore it to you”. The mosque is not the place in which the animals harbor. In principle: the mosque is not built for making lost property announcements.
The same ruling applies for selling, buying, reading poetry, the controversy that leads to adversity, laughter and speech with a loud voice, the idle talk, and sleeping in the mosque for no pressing reason, etc.
In addition to the other matters which contradict the sanctity of the mosque and are incompatible with its Highness and majesty.