Can a church be turned into a mosque?

A building, not a person

In Islam, holiness comes from the worship done in a place, not from the bricks. The Prophet ﷺ said that the whole earth has been made a place of prayer and a means of purification for him and his community (Sahih al-Bukhari 335). So a hall that was once a church, a cinema, a pub or a warehouse can become a mosque once it is set aside for prayer. When a congregation in the West shrinks and a church is put up for sale, buying it for Muslim prayer is a normal property deal.

It must be done fairly

Islam does not allow taking a place of worship by force from a living community. The Quran speaks of protecting houses of worship:

Christians and Jews living under Muslim rule kept their churches and synagogues by agreement. A famous report says Caliph Umar declined to pray inside the Church of the Holy Sepulchre in Jerusalem, so that later Muslims would not claim it as a mosque. Today, the rule is simple: buy it, rent it or receive it lawfully, follow planning law, and treat neighbours with respect. See Is there freedom of religion in Islam?

What changes inside

• Images and statues are removed or covered in the prayer area, and crosses are taken down.
• The qibla is worked out, since church naves usually face east, not Mecca. Rows are often set at an angle across the hall.
• Pews come out and carpet goes in, and wudu facilities are added.
• Some features stay, like stained glass with plain patterns, if they hold no religious images.

Real examples

The Brick Lane Jamme Masjid in East London began as a Protestant chapel in 1743, later became a synagogue, and has been a mosque since 1976. Across Britain, the Netherlands and the US, many smaller mosques also meet in former church buildings. Some Muslims feel uneasy about this, but scholars generally see no problem when the sale was fair. Praying in a church that is still in use is a different question. See Can I pray in a church if there's no mosque nearby?