1. Remain calm and dignified while in the musjid and do not be unmindful of the sanctity of the musjid. Some people, whilst waiting for the salaah to commence, fidget with their clothing or play with their cell phones. This is against the honour and respect of the musjid.
2. Assist in keeping the musjid clean and tidy.
عن أبي سعيد الخدري رضي الله عنه قال قال رسول الله صلى الله عليه وسلم من أخرج أذى من المسجد بنى الله له بيتا في الجنة (سنن ابن ماجة، الرقم: 757)
Hazrat Abu Sa’eed Khudri (radhiyallahu anhu) reports that Hazrat Rasulullah (sallallahu alaihi wasallam) said, “Whoever removes some dirt from the musjid, Allah Ta’ala will build for him a magnificent palace in Jannah.”
3. Do not bring into the musjid infants, insane people or children who are underage and do not know the aadaab (etiquettes) of the musjid.
4. While in the musjid, remain constantly engaged in the aa’maal of the musjid e.g. zikr of Allah Ta’ala, tilaawah of the Quraan Majeed, salaah, etc.
5. Apart from going to the musjid to perform salaah, if there is a program being held in the musjid, then one should make the intention of going to the musjid to acquire the knowledge of Deen. If one has the ability to teach Deen then one should make the intention of coming to the musjid to impart the knowledge of Deen to people if one finds the opportunity to do so.
عن أبي هريرة رضي الله عنه قال سمعت رسول الله صلى الله عليه وسلم يقول من جاء مسجدي هذا لم يأته إلا لخير يتعلمه أو يعلمه فهو بمنزلة المجاهد في سبيل الله ومن جاء لغير ذلك فهو بمنزلة الرجل ينظر إلى متاع غيره (سنن ابن ماجة، الرقم: 227)
Hazrat Abu Hurairah (radhiyallahu anhu) mentions, “I heard Rasulullah (sallallahu alaihi wasallam) saying, “Whoever comes to this musjid of mine, and he does not come for any purpose besides learning some good or teaching some good, then he is like the one who is striving in the path of Allah Ta’ala, and the one who comes to the musjid for any other purpose (besides the worship of Allah Ta’ala), then he is like a man who looks at the merchandise of others (being sold, yet he does not earn anything).”
عن أبي هريرة قال قال رسول الله صلى الله عليه وسلم من أتى المسجد لشيء فهو حظه (سنن أبي داود، الرقم: 472)
Hazrat Abu Hurairah (radhiyallahu anhu) reports that Rasulullah (sallallahu alaihi wasallam) said, “Whoever comes to the musjid for some purpose, then that will be his share (i.e. he will be rewarded according to his intention).”