Q: We have a charitable institution offering housing for widows, orphans, and the disabled. The institution receives huge amounts of Zakah (obligatory charity) from Muslims in our country. After paying all the necessary expenses of the institution, there is a surplus from the Zakah.First:Is it permissible according to the Shari`ah (Islamic law) to keep the remaining money for other years?Second:Do we have to pay Zakah on this money?Third:Is it permissible to spend this money on poor Muslims outside the institution?Fourth:If we invest this money in building houses for rent, is it permissible for us to spend the revenue on Masajid (mosques) and their Imams (persons who lead congregational Prayer)?Fifth:Thanks to the assistance of the Islamic Development Bank (IDB), the institution built a building and, for certain conditions, it is renting out part of this building. Is it permissible for us to spend the rental on Imams of the Masajid? We need your advice in a written letter. May Allah grant you the best reward for serving Islam and Muslims!