The constitution guarantees freedom of religion, including the freedom to practice it in public and to manifest religious opinions, as long as no crime is committed in exercising that freedom. The constitution prohibits compulsory participation in or attendance at church services or observance of religious days of rest and stipulates that religious marriages must be preceded by a civil marriage ceremony to be recognized by the state. The constitution provides for the regulation of relations between religious groups and the state, including the role of the state in appointing and dismissing religious clergy and the publication of documents by religious groups, through conventions between the state and individual religious groups. The constitution stipulates the state shall pay the salaries and pensions of religious clergy as regulated by law. The government only recognizes and pays the salaries and pensions of clergy from religious communities that have signed a convention with the government.
To qualify for a convention with the state, a religious community must establish an official and stable representative body with which the government can interact. The following religious groups have signed conventions with the state, and therefore receive support: Catholic; Greek, Russian, Romanian, and Serbian Orthodox; Anglican; the Reformed Protestant Church of Luxembourg; the Protestant Church of Luxembourg; and the Jewish community. Groups without signed conventions may operate freely but receive no state support.
Religious instruction in public schools is managed locally, coordinated between representatives of the Catholic Church and 105 communes. Parents and pupils may choose between instruction in Catholicism or an ethics course. There are government-salaried Catholic religious instructors at all levels in public schools. Schools grant exemptions from the Catholic or ethics instruction on an individual basis.
The government subsidizes all private religious schools affiliated with a religious community that has signed a convention with the state, including subsidies for facilities expenses and in some cases teacher salaries. The government also subsidizes a Catholic seminary.