Is it prohibited to let animals (cats) enter the mosque?
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Cats are pure and their entering the mosque does not cause harm in terms of purity since it has been narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said, "They (cats) are not impure, they are of those who frequently go around you." [Maalik in Al-Muwatta’]
However, if cats entering the mosque cause harm or their hair falls in a way that affects the cleanliness of the mosque, then they should be banned. This is even more stressed if it is feared that their urine or stool may contaminate the mosque, in which case it becomes prohibited to let them in.
Allah knows best.
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