Fiqh of Masjid (Mosque) & Musalla

Fiqh of Masjid (Mosque) & Musalla
What exactly is a masjid (mosque)? Is there a difference between a masjid (mosque), musalla, and jamat khana, etc? These are questions which need detailed discussion.
Nowadays, in the west, many Islamic Centers being managed include, among other things, a prayer hall, musalla, or jamat khana. Some communities rent an industrial unit, a store front, a house, or an apartment in which members of the Muslim community gather to perform congregational prayer (and in many cases social activities). Many communities actually have purchased property which they consider their masjid (mosque).
Which of the above can technically be considered a masjid (mosque), and what are the related rulings?
There is a difference between a masjid (mosque) and a musalla (or jamat khana). A musalla (or jamat khana) literally means a place where prayer is performed or where congregations are held, or worded differently, any temporary place in which worshippers congregate to perform their prayers. A musalla is also a place that has not been made an endowment or not yet intended to become a permanent masjid (mosque) until the Last Day. In many cases, it is a temporary place from which the community will transfer once they find a more suitable, convenient, or permanent location. Though Muslims today commonly refer to their “musalla” as their “masjid (mosque),” which the literal meaning of masjid (mosque) (a place where the prostration is made) allows, a musalla cannot technically be considered a legal [shar‘i] masjid (mosque). Likewise the reward for prayer in a musalla is not the same as in a proper masjid (mosque).
The masjid (mosque)
The masjid (mosque) is a sanctified area, in which the rewards of prayers in congregation increase 25 to 27 times and where the mercy of Allah descends. It is considered the best of places by the Messenger of Allah (upon him be peace). Ibn Abbas (may Allah be pleased with him) relates:
masjid (mosque)s are the houses of Allah on the earth. They shine up to the inhabitants of the heavens just as the stars in the sky shine down to the inhabitants of the earth (Tabarani).
A masjid (mosque) is normally made into a waqf or endowment (sometimes difficult to establish depending on the legal connotations of endowment in some countries). However, once a masjid (mosque) is erected, it will always be a masjid (mosque) and the property of Allah. It cannot return to being the property of any person or community even those who may have paid for establishing it. Allama Haskafi writes:
If the inhabitants surrounding the masjid (mosque) wither away and the masjid (mosque) becomes desolate, it will still remain a masjid (mosque) according to Imam Abu Hanifa and Imam Abu Yusuf until the Last Day, and the fatwa is on this opinion (Hawi al-Qudsi)” (al-Durr al-Mukhtar 3:371).
The Messenger of Allah, Prophet Muhammad (peace be upon him) said:
All the earth will disappear on the Day of Judgment with the exception of the masjid (mosque)s for they will join with one another (Suyuti, Jami al-Shaghir).
Designation of a masjid (mosque)
A masjid (mosque) (to become a masjid (mosque)) must be formally designated by the committee or persons in charge. They do this by defining the area it will occupy and its boundaries. Along with this they can designate other adjoining areas to be used as bathrooms, lobby, storage, etc. The latter however will be considered the auxiliary areas of the masjid (mosque) and, though part of the endowment, will not classify as “masjid (mosque)” area that was previously defined by the committee.  Therefore, it is possible, for example, to designate only the front half of a large hall (i.e. the first 10 rows) as the "masjid (mosque)", while the rest of the hall is classified as a musalla. Once the front half has been designated as such, then that part, both above and below it, becomes a shari masjid (mosque). This means that neither above it nor below it on any floor can be used for anything but as a masjid (mosque). Hence, all rulings that apply to a masjid (mosque) will now apply to the exact same area directly below it on each of the lower floors (including the basement); and likewise on all floors above it. Constructing toilets, bathrooms, or holding any non-suitable activities above or below the "masjid (mosque)" area will also be impermissible. However, it is permissible to have toilets or bathrooms constructed out of the boundary of the designated masjid (mosque) area on any of the floors, since those areas will be considered the auxiliary area of the masjid (mosque) and not technically the masjid (mosque) itself. Allama Haskafi writes in his well-accepted text al-Durr al-Mukhtar:
“It is prohibitively disliked to have sexual intercourse above the masjid (mosque). Likewise it is disliked to urinate or defecate above it because it is a masjid (mosque) to the peaks of the heavens (Ibn Abidin adds, “Likewise to the recesses of the earth below”) … it is disliked to enter any impurity into it.… [However] these are not disliked above a room which has been just set aside as a masjid (mosque) [in a person's home] nor in the room itself, since that is not a shar‘i masjid (mosque)… It is permitted for those in a seminally defiled state or menstruating women to enter into it [i.e. a musalla or place especially prepared for Eid or funeral prayer] just as is permitted into the extended yard of the masjid (mosque) [i.e. the overflow area].… (al-Durr al-Mukhtar with Radd al-Muhtar 1:441-442).
Hence, no area of the actual masjid (mosque) prayer area can be excluded from the masjid (mosque) once designated as a masjid (mosque). However, before the plans are finalized and the area is designated a masjid (mosque), portions can be excluded from any of the floors above or below where the masjid (mosque) will be, to be used for something else that is related to the masjid (mosque), for instance, a storage area, office for the imam, a basement for storing masjid (mosque) amenities, a shop to bring in income for the masjid (mosque), etc. Ibn Abidin writes in his Radd al-Muhtar:
If they build a room above it for the imam then there is nothing wrong with that, because that is part of the welfare of the masjid (mosque). However, once the construction [designation] of the masjid (mosque) is completed then they want to add a room, it will be prohibited [to change the designated masjid (mosque) area and add a room for something else in it]. If the committee states that we had intended to do such, their statement will not be upheld [in court] (Radd al-Muhtar 3:371).
Likewise the Egyptian jurist Ibn Nujaym writes:
It states in the Mujtaba that it is not permitted for the guardian of the masjid (mosque) to build shops in the masjid (mosque) or in its courtyard [i.e. the courtyard in which salats are performed during summer in hot countries - also known as the external masjid (mosque)] (al-Bahr al-Raiq 5:249).
Storage Areas and Water Reservoir Above or Below a masjid (mosque)
A masjid (mosque) can have a storage area above or below the actual prayer hall. The storage space below the prayer hall however must be used solely for the amenities of the masjid (mosque) and must have been designated as such in the masjid (mosque)'s design phase. Likewise, it would be permitted to have constructed a water reservoir underneath the masjid (mosque) (as in some Muslim countries). It states in the al-Durr al-Mukhtar:
If they make a basement beneath the masjid (mosque) for its welfare [however, Allama Ibn Abidin adds here that this should be of limited area], it would be permissible just as is in the masjid (mosque) in Jerusalem (al-Durr al-Mukhtar ma’a ‘l-Radd al-Muhtar 3:370).
A Residence or Bathrooms Above or Below a masjid (mosque)
Although it is permissible to allocate certain parts of the masjid (mosque) as a room for the imam and other uses from the original plan, bathrooms or a complete apartment for the imam should not be planned directly above the actual masjid (mosque) area, even during the masjid (mosque)'s initial design phase, since it is impermissible to have sexual relations, relieve oneself, etc., above or below a masjid (mosque). In any case, adding a residence or office to the existing masjid (mosque) area will not be permissible after the masjid (mosque) area is designated. Allama Ibn Abidin writes:
"It remains [to be ruled], whether it would be permissible if the person making the endowment designates lavatories [bayt li ’l-khala’] to be directly beneath the masjid (mosque), as is the case in masjid (mosque) Mahallat al-Shahm in Damascus. I have not seen a specific ruling on this. Yes, it states in the Chapter of Endowments [of al-Durr al-Mukhtar] 'If they make a basement beneath the masjid (mosque) for its welfare it would be permissible' so ponder" (Radd al-Muhtar 1:441).
Ibn Abidin however only mentions this analogy between a storage basement and bathrooms in passing, stating that it is an issue in need of further deliberation. It is not based on any strong analogy.
Islamic Centers and Musallas Today
In the case of large Islamic centers today, which include a prayer hall, the prayer hall area could be considered the shar'i masjid (mosque), if it has been intended and designated as such. However, the adjacent rooms, such as the lobby, dining hall, children's room, gymnasium, or offices would be considered as supplementary or extensions of the masjid (mosque) and hence, not part of the shar'i masjid (mosque) area, even though they would be part if the endowment [waqf] (i.e. not returnable to any one's ownership), but the rulings would be different for the two as we will highlight below.
Women in Menstruation
A menstruating women or one who is experiencing post natal bleeding or a person in a seminally defiled state is prohibited from entering into a masjid (mosque). The Prophet Muhammad (peace be upon him) said:
I do not make the masjid (mosque) lawful for the menstruating women or the one experiencing post natal bleeding (Abu Dawad, Ibn Maja, Tabarani, Zayla'i has considered it sound [hasan] 1:193-194).
Young Children in the masjid (mosque)
It is unlawful [haram] to bring in infants or young children into the masjid (mosque) if there is a possibility of them polluting the area of the masjid (mosque). If they are in diapers and less likely to pollute any part of the masjid (mosque), it will still be somewhat disliked (makruh tanzihan) to bring them as they could be carrying filth in their diapers (Radd al-Muhtar ’ala ‘l-Durr 1:441, Al-Ashbah wa ‘l-Naza’ir, al-Qawl fi Ahkam al-masjid (mosque) 407). The Messenger of Allah (peace be upon him) said:
Keep your infants and the insane away from your masjid (mosque)s (Sunan Ibn Maja, babu ma yukrahu fil-masjid (mosque)).
Sleeping & Eating in the masjid (mosque)
It is disliked to sleep or eat in a masjid (mosque) without the intention of itikaf or unless one is a traveler (al-Ashbah wal-Nazair 407)
Congregation for Five Daily Prayers in the masjid (mosque) is a Communal Obligation
A congregation for the five daily prayers have to be established in a masjid (mosque) otherwise the local inhabitants would be sinful for negligence, since it is a wajib to perform the congregational prayers for the locals in the masjid (mosque). Allama Ibn Abidin writes regarding tarawih prayer which is a confirmed sunna and not wajib:
The apparent purport of their [jurists] statement is that it is a communal sunna to perform it [tarawih] in congregation in the masjid (mosque), to the extent that if they performed it in congregation in their homes, and no congregation took place in the masjid (mosque), they would all be sinful (Radd al-Muhtar 1:473).
Hence, if this is the case for a confirmed sunna congregation, it would be more binding to have a congregation for every obligatory prayers in each locality. The Messenger of Allah (upon him be peace) said:
There is no salat for the neighbor of the masjid (mosque) except in the masjid (mosque) (Daraqutni, Hakim from Kashf al-Khafa’).
Conversation in the masjid (mosque)
It is likewise disliked [makruh] for one to speak about worldly affairs in the masjid (mosque), Umar Farooq (may Allah be pleased with him) had designated a special place outside the masjid (mosque) where people could go and talk.  Ibn Abidin writes:
(It is disliked to speak in the masjid (mosque)) this is  regarding that talk which is of [a] permissible nature, [and] not regarding other than that which would warrant much greater sin (i.e. if one were to speak of it in the masjid (mosque)) (Radd al- Muhtar 5:269).
The Musalla or Temporary Place of Prayer
All the above restrictions (i.e. that it is disliked to speak of worldly matters in the masjid (mosque), etc.) do not technically apply to a musalla since it is a temporary place for worship. Hence, it can have apartments, bathrooms, etc., above or below it; or itself even turned into such (i.e. an apartment), once it is no longer used as a musalla. However, it is recommended to treat it as a masjid (mosque), since it is being used for similar purposes.
A third floor musalla within an industrial complex, which has other activities and businesses operating on the other floors (basement included), cannot be considered a shar'i masjid (mosque), but rather comes within the definition of a musalla. Allama Haskafi writes:
If the basement was designated for any other use [i.e. not for the masjid (mosque)] or he [the owner] made a room above it and faced the door of the masjid (mosque) to the street [meaning he made it separate], then it cannot be a masjid (mosque). Hence he may sell it… [if he wishes, since it does not become an endowment] the same as if he had made [a portion from] the middle of his home into a masjid (mosque), and permitted for the adhan to be called therein - it would not become a masjid (mosque).
Allama Ibn Abidin comments on this by saying:
The reason for the place not being a masjid (mosque) is because the additional rooms are not designated for the welfare of the masjid (mosque). This is explicitly mentioned in the Is'af, where it says, “If the basement or the floor above it is endowed for the benefit of the masjid (mosque) or they were properly endowed for that then it would become a masjid (mosque) (Shurunbulaliyya). It states in al-Bahr [al-Ra’iq] that the summary of this [issue] is that it is a condition for it being considered a masjid (mosque) that the lower and upper floors need to [also] be a masjid (mosque), so that the rights [and ownership] of people is waived from it, as Allah says 'And verily the masjid (mosque)s are for Allah' (Radd al-Muhtar 3:370).
Although similar laws should be observed in a musalla as in a masjid (mosque), since it is emulating a masjid (mosque), it is not legally necessary. Therefore:

    It would be permissible for menstruating women to enter into a musalla to attend classes or lectures.
    Performing prayer therein would not hold the same reward as praying in a masjid (mosque) although it would be more than in the home. A hadith related by Ibn Hajar al-Asqalani from Abdullah ibn Amr ibn al-As states that the reward for a congregation with one’s family members (aside from in a masjid (mosque)) holds 15 times the reward of praying alone, whereas praying it in the congregation in the masjid (mosque) holds twenty five times the reward. Ibn Hajar al-Asqalani concludes that the 25 times extra reward is confined to performing it in congregation in the masjid (mosque) and not in a congregation performed at home. See Fath al-Bari 106, Mirqat al-mafatih 3:145, and al-Bahr al-raiq (1:346)
    It would be permissible to eat or sleep in a musalla without having the intention of itikaf, which is necessary in the masjid (mosque) for one to eat or sleep.
    One can also perform Tahiyyat al-masjid in a musalla.

A useful setup for women's prayer could be that there be two room: one connected to the back of the men's prayer area, which could be intended as being included in the shar’i masjid (mosque); and another room behind the first room, which could be a musalla or a multi purpose room for menstruating women or women with children to stay in.