With regard to the employer and the employee, it is not a condition for either of them to be a Muslim. So a Muslim is absolutely allowed to hire a non-Muslim, by the evidence of the action of the Prophet (pbuh) (pbuh) and the consensus of the Sahabah at the hire of non-Muslims in any allowed (Mubah) action, including the works of the State. The Prophet (pbuh) (pbuh) hired a Jew as a clerk, and another Jew as an interpreter, and He hired a polytheist (Mushrik) as a guide. Abu Bakr and ‘Umar hired Christians as accountants for the funds. As it is allowed for the Muslim to hire a non-Muslim, the Muslim too is allowed to be hired by a non-Muslim to perform a permissible action. But prohibited work must not be performed whether the employer is a Muslim or a non-Muslim. So the Muslim is allowed to be hired by a Christian to work for him. This must not include work where a Muslim is being subjugated to the Kafir in order for Him to be humiliated. Rather it is the hiring of himself to another person, on a matter that is allowed, without belief in Islam being a condition for the employer or the employee. Ali (ra) hired himself to a Jew for drawing water for Him at a wage of one date for every bucket of water, and He informed the Prophet (pbuh) (pbuh) about it, and He did not prohibit it. Also because hiring is a contract of exchange that does not include the humiliation of the Muslim. However, for work which is meant to bring us nearer to Allah the Supreme, it is a condition that the person hired be a Muslim. Examples include leading the prayer, performing the Adhan, pilgrimage, distributing Zakat and teaching Qur’an and the Hadith. Because these are not legally valid except from a Muslim, so no one is hired to perform them except a Muslim. The reason (Illah) in these actions is that they are not valid except from a Muslim. But if the works which are meant to bring us nearer to Allah (swt) are valid to be performed by a non-Muslim, then it is valid to hire Him for doing them. In summary: if the works are considered by the employer as a sort of seeking the nearness to Allah, but are not considered as such by the employee then they have to be examined. If they are not valid except from the Muslim such as judicial acts (Qadha’a), then the non-Muslim is not allowed to be hired for performing them. But if it was valid for the non-Muslim such as fighting, then He is allowed to be hired for doing that. So the Dhimmi (non-Muslim) is allowed to be hired for fighting and his wage is paid from the Bait ul- Mal.