The origin of the mosque as both a distinctive space and a structure is linked to religious restrictions and to the Muslim conquest. The small communities of conquerors, united by the new faith and immersed within populations of different religions, prayed in these mosques, where they listened to the "reciters of the Revelation" and the exhortations to conquer in the name of Allah.
Sacredness is the essential dimension of the mosque, an enclosed space separate from the profane world. This attribute is expressed through the Arabic term haram, which means something that is both prohibited and separate. Before Islam, the term designated the reserved enclaves around sanctuaries or wells. This area was protected from violence. In the Tradition, haram indicates any holy place of Islam, with the three sacred mosques at the top. The important haram(s) are all located in the Land of the "Two Qibla-s", Arabia with Mecca and Medina, and Palestine (Jerusalem).
The mosque is the place for the "abandonment of the self" and the glorification of a Transcendent God in a sacred space, guided by the qibla (the direction of Mecca, "Qibla of the universe", Quran 3-90), a focal point toward which are turned the body and the spirit of the worshipping believers. After the hegira, the first qibla was established by Muhammad in the direction of the "sacred Temple" of Jerusalem and then toward Mecca after the violent break in relations with the Jewish tribes of Medina. Etymologically speaking, the term masjid is the place of prostration to complete an act of worship. It is first a place of prayer. According to a hadith: "The whole earth is a mosque". Every place of prayer is a masjid. Mosques can be found in different sizes, designs and aspects: small oratories in neighbourhoods and private or public prayer rooms, considered mosques after the moment of completion of canonical prayers.
The sacredness of the place is conferred by the behaviour and by the ritual of separation from the profane world: women cover themselves and all the faithful perform ablutions and remove their shoes before entering. Sometimes, the sacralisation of the place is connected to the presence of relics, the body of a saint or even precious objects, Qurans and poems, such as those by sheikh Amadou Bamba in a small mosque in Touba, Senegal.
Muslims had to "invent" the mosque. Nothing in the Quran had dictated an architectural model. The term "mosque" is often found in the Book, but it does not refer to any specific type of architecture. The mosque was designed based on the design of the home, the Dar, an enclosed and built space and frame encompassing a court and housing area. Muslims turned the house of the Prophet in Madinah into the archetype of the mosque. This private space was redesigned according to the historic and cultural context, while respecting the tradition of the enclosed space of the home and its social role: the mosque is a djami' (that brings together), a place for praying, preaching and studying. Several elements (decoration, architecture, materials, etc.) were borrowed to fulfil the needs of a new community united by the same Law.
There are no ritual objects that are required for the practice of worship. Islam did not generate a liturgical art, but it brought together certain "strong" elements: the minaret, a symbol of faith and power, and a symbolic and decorative element that appears under the Omayyads, and especially the mihrab or the facilities for performing the ablutions.
In pre-Islamic literature, the mihrab had the meaning of “hollow” or "niche". The mihrab is a void in contrast to the niche of a synagogue, which houses the ark of the Law and the five scrolls of the Torah. As a visual marker, it indicates the direction of the qiblah, but the first mosques did not have a mihrab. The great Sufi Ibn 'Arabi (who died in 1240) defined the qibla as a marker which helps reach the Sakinah, peace, serenity and the manifestation of divine presence. The mihrab is the gate leading to the light, " God guides to His light whom He pleases.” (Quran 24,35). In the mystical vocabulary, the niche also symbolizes the cave, which hides the heavenly reality which will be unveiled to the initiate.
Some authors attribute a commemorative function to the mihrab. It was a "hollow mold with the presence of the Prophet". The first mihrab was built under the Omayyads during the reconstruction of the Madinah mosque (707-709) as a remembrance of the place where Muhammad stood to pray and preach. It also had the function of a "gold Book" whose inscriptions were connected to the profession of faith, the message, the Prophet’s mission and the uniqueness of God. There were also Quranic verses on light and blessings in honour of the sponsor.