Do non-Muslims have the right to call people to their religion?
Q. If Muslims have the right to call others to Islam, why do non-Muslims not have the right to call others to their religions?
A. Calling people to Islam and to worship none but Allah (Exalted be He) is the mission of Allah's Messengers and the Muslims coming after them.
The Muslims, after the mission of Prophet Muhammad (peace be upon him), undertake this task, as they are those who follow the revelation sent down by Allah (Exalted be He). That is why they call people to the right path as a way to worship Allah (Exalted be He) and to follow the footsteps of their Prophet Muhammad (peace be upon him) and the preceding prophets (peace be upon them).
Furthermore, the practice of calling people to Islam is a mercy for all creatures and sympathy for them regarding the chastisement set by Allah (Exalted be He) for the disobedient. Also, calling people to Islam signifies the establishment of the call which is dear to Allah (Exalted be He) to leave its opponents with no excuse of ignorance.
As for non-Muslims, whatever their religions and beliefs are, it is not permissible for them to call people to their false and corrupt religions. This is because the one who follows the right path is in no need to follow corrupt religions. Moreover, it is not permissible for Muslims to allow the followers of corrupt religions to call people to their false religions. This is because calling people to disbelief means abolishing Islam, denying the Qur'an and the Prophethood of Muhammad (may peace be upon him), and approving of the worship of crosses, idols, fire and others false deities along with Allah, may He be Glorified and Exalted above such falsehoods.
It is not acceptable to permit the call to the worship of Allah alone and the worship of other deities at the same time; the call to belief in Allah and His Messenger and the denial of Allah and His Messenger at the same time; or the call to hate the disbelievers and their traditions and the call to love and be loyal to the disbelievers and their traditions at the same time. This is not acceptable at all.
Permanent Committee Fatwas > Volume 1 (`Aqidah) > Tawhid-ul-Uluhiyyah > Calling to a religion other than Islam, 4th question of Fatwa no. 21166