section_path: Medinan years/Building the religious community in Medina
section_name: Building the religious community in Medina
paragraph_text: Building the religious community in Medina
  
  A few days after settling in Medina, Muhammad negotiated for the purchase of a piece of land; upon this plot, the Muslims began constructing a building that would become Muhammad's residence as well as a community gathering place (masjid) for prayer (salat). Tree trunks were used as pillars to hold up the roof, and there was no fancy pulpit; instead, Muhammad stood on top of a small stool to speak to the congregation. The structure was completed after about seven months in April 623, becoming the first Muslim building and mosque; its northern wall had a stone marking the direction of prayer (qiblah) which was Jerusalem at that time. Muhammad used the building to host public and political meetings, as well as a place for the poor to gather to receive alms, food, and care. Christians and Jews were also allowed to participate in community worship at the mosque. Initially, Muhammad's religion had no organized way to call the community to prayer in a coordinated manner. To resolve this, Muhammad had considered using a ram's horn (shofar) like the Jews or a wooden clapper like the Christians, but one of the Muslims in the community had a dream where a man in a green cloak told him that someone with a loud booming voice should announce the service by crying out " allahu akbar " ("God is greater") to remind Muslims of their top priority; when Muhammad heard about this dream, he agreed with the idea and selected Bilal, a former Abyssinian slave known for his loud voice.