Article 15 of the Constitution of the Republic of Singapore guarantees freedom of religion in Singapore. Specifically, Article 15(1) states: "Every person has the right to profess and practise his religion and to propagate it."
The terms profess, practise and propagate are not defined in the Constitution, but cases from Singapore and other jurisdictions may shed light on their meaning. The word profess in relation to a religion was defined in a 1964 Singapore case not involving the Constitution as meaning "to affirm, or declare one's faith in or allegiance to". A 2001 Malaysian decision suggested that the profession of religion does not encompass the renunciation of a religion or the profession of an irreligious viewpoint. As regards the word propagate, in 1977 the Supreme Court of India held that it confers on an individual the right to transmit or spread his or her religion by an exposition of its tenets, but not the right to convert another person who holds a pre-existing religious belief to one's own religion. These issues have not yet come before the Singapore courts for determination. On the other hand, in 1999 the Court of Appeal attempted to draw a line between religious practices and secular facts, taking the view that singing the National Anthem and saying the National Pledge were the latter. Thus, rules that compelled a teacher to engage in these activities in an educational institution could not be regarded as having infringed his right to practise his religion.
Freedom of religion under Article 15(1) is not absolute as it is qualified by Article 15(4) of the Constitution, which provides that the rights secured by Article 15 do not authorize any act contrary to any general law relating to public order, public health or morality. These limitations upon the freedom of religion are an important aspect of Singapore's secularism. The Singapore courts have interpreted the term public order to be equivalent to the concepts of "public peace, welfare and good order" referred to in section 24(1)(a) of the Societies Act (Cap. 311, 1985 Rev. Ed.), rather than taking the narrower view that public order means freedom from unlawful physical violence. There has also been academic criticism of the fact that the courts have not applied any form of balancing test to determine whether freedom of religion has been reasonably restricted. On the contrary, where national security is said to be involved, the courts have deferred to the Government as to the necessity for the restrictive legislation. The terms public health and morality in Article 15(4) have yet to be judicially interpreted.