Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 2 months ago

Non Muslims are different types;

1. People of Book who are Christians and Jewish etc who have different rules in entering Masjid. The obligatory precaution prevents letting them inside a Masjid.
2. Non Muslims who are not People of Book e.g Mushrik or denying religion etc, are definitely not allowed to enter any Masjid.