The recent execution of Sheikh Nimr al-Nimr in Saudi Arabia and the resulting anti-Iran and anti-Shi'ite rhetoric in the Arab gulf states and throughout the Sunni world suggest that Sunni-Shi'ite conflict is a developing problem.

On the other hand, the Amman Message, issued more than 10 years ago, is a historic statement expressing the desire of Muslims to be united and to live lives free of sectarian strife. It is a formal statement by Muslims of a pluralistic mutual recognition and respect, and one that deserves to be highlighted in this time of tension.

The first decades of the 21st century will be known as a period of great hostility between the two major denominations of Islam - the Sunnis who form the majority of the global Muslim population, and the Shi'ites, who make up about 20 per cent. Shi'ites are in the majority in Azerbaijan, Bahrain, Iran and Iraq. They also form significant, influential minorities in countries such as Lebanon, Kuwait, Turkey, Afghanistan and Saudi Arabia.

The history of Islam is littered with violence and hostility between Sunnis and Shi'ites. The confrontations were often initiated by Sunni rulers and, sometimes, by the religious elite. Shi'ites are divided into three major groups - the Ithna 'Ashari, the Ismaili and the Zaidi. The Ithna 'Asharis or the Twelver Shi'ites are the demographically and culturally dominant Shi'ite group. They form the majority of Muslims in Azerbaijan, Bahrain, Iran and Iraq. But there are also important Shi'ite minorities in Lebanon, Kuwait, Turkey, Afghanistan and Saudi Arabia.

In modern Saudi Arabia, which has a majority Sunni population, Shi'ites have suffered from much religious, political and economic marginalisation and persecution. They are poorly represented in the political system, excluded from certain positions in the armed forces and the security services, and have often faced legal and other forms of discrimination.

The leading Saudi cleric, Sheikh Abdul Aziz bin Baz, declared Shi'ites as apostates - people who have abandoned their religious belief.

Sheikh Abdallah Abd al-Rahman Jibrin, a member of the Senior Council of Ulama, the country's highest religious authority, sanctioned the killing of Shi'ites.

For the last two decades, Shi'ites in Malaysia had come under increasing scrutiny by the religious authorities and have also been subject to persecution. In the last few years, Shi'ites had been subjected to violence in Bahrain, Pakistan, Indonesia and Egypt. Nor is the violence one way - in Iraq, it is Sunnis who have been the target of Shi'ite militias.

Both Sunnis and Shi'ites have been victims of Salafi-jihadi violence in the so-called Islamic State in Iraq and Syria, where barbaric acts of violence were also perpetrated against Christians and other religious minorities. Salafi-jihadists adopt a puritanical and violent interpretation of Islam.

HISTORY OF TOLERANCE

Despite such a history, it would be wrong to suggest that Sunnis and Shi'ites have been in a state of protracted conflict throughout history. While conflict exists, for the most part, Sunnis and Shi'ites have lived in a context of tolerance and even pluralism, rather than animosity.

While there are theological and ideological differences that have always existed between Sunnis and Shi'ites, today's sectarian conflicts have more to do with the manipulation of sentiments for the sake of political and material interests, rather than religious ideals. It is here that the Amman Message has the potential to play a positive role in mobilising Muslim leaders and communities towards intra-Muslim peace.

The Amman Message, calling for tolerance and unity among the Muslims of the world, was first issued on Nov 9, 2004, by King Abdullah Al-Hussein of Jordan. It deals with three fundamental issues known as the "Three Points of the Amman Message". Its early stages took the form of a statement by King Abdullah that declared what Islam is and is not, and what actions represent Islam and do not.

To give the statement religious authority, King Abdullah asked three questions of 24 senior ulama, or religious clerics , from around the world, who represented the main schools and branches of Islam: Who is a Muslim?; Is it permissible to declare someone an apostate (takfir)?;Who has the right to undertake the issuing of fatwas (legal rulings)?

The fatwas provided by the scholars formed the basis for an international conference of 200 leading Muslim scholars convened in July 2005 by King Abdullah in Amman. There, the scholars unanimously issued a ruling on the three fundamental issues, known as the "Three Points of the Amman Message".

The first concerns the validity of all eight madhhabs, or legal schools, of Sunni, Shi'ite and Ibadhi Islam; of the Ash'arite school of theology; of Sufism, and of true Salafi thought. Ibadhis make up yet another sect of Islam and are found mainly in Oman. Ash'arism refers to Sunni theological doctrine, while Sufism refers to the mystical dimension of Islam. In this way, a precise definition of who a Muslim is was arrived at.

The second fundamental issue concerns the prohibition of takfir, or the declaration of apostasy between Muslims. The third issue concerns the preconditions for the issuing of fatwas. The objective here was to expose ignorant and illegitimate opinions and rulings in the name of Islam.

The Three Points were unanimously adopted by the heads of state of the Muslim world at the Organisation of the Islamic Conference summit in Mecca in December 2005. The Three Points were also unanimously adopted by another six international Muslim scholarly assemblies. This culminated in the International Islamic Fiqh Academy of Jeddah in July 2006. In total, more than 500 leading Muslim scholars from 84 countries endorsed the Amman Message. It states:

"Whosoever is an adherent to one of the four Sunni schools (Mathahib) of Islamic jurisprudence (Hanafi, Maliki, Shafi'i and Hanbali), the two Shi'ite schools of Islamic jurisprudence (Ja'fari and Zaydi), the Ibadhi school of Islamic jurisprudence and the Thahiri school of Islamic jurisprudence, is a Muslim.

"Declaring that person an apostate is impossible and impermissible. Verily his (or her) blood, honour and property are inviolable.

"Moreover, in accordance with the Shaykh Al-Azhar's fatwa, it is neither possible nor permissible to declare whosoever subscribes to the Ash'ari creed or whoever practises real Tasawwuf (Sufism) an apostate.

"Likewise, it is neither possible nor permissible to declare whosoever subscribes to true Salafi thought an apostate.

"Equally, it is neither possible nor permissible to declare as apostates any other group of Muslims who believes in God, Glorified and Exalted be He, and His Messenger (may peace and blessings be upon him), the pillars of faith (Iman), and the five pillars of Islam, and does not deny any necessarily self-evident tenet of religion."

NEED FOR POLITICAL WILL

In his foreword to the Amman Message, King Abdullah stressed that the consensus that created it "does not represent the opinion of one man, one ethnic group, one country, or even a group of countries... It represents a unanimous agreement by all Muslims everywhere as represented by their acknowledged most senior religious authorities and political leaders".

But why has sectarianism among Muslims, particularly that concerning Sunni-Shi'ite relations, deteriorated during the last few years? Indeed, the Amman Message has not been taken seriously by many of the countries that endorsed it. These include Saudi Arabia, Bahrain, Malaysia, Nigeria and Iraq.

A certain measure of political will is required to put into practice the values that inform the Amman Message.

Long before the Amman Message was drafted, the Sultanate of Oman had displayed such will. Although the Ibadhis of Oman make up about 75 per cent of the population, Oman is probably the one country that allows for the greatest harmony between Sunnis, and Shi'ites who make up the rest of the population. Omani basic law prohibits discrimination based on religion and protects the rights of different religious communities to practise their religions on the condition there is no disruption of public order.

Many Muslim countries have failed to live up to the ideals expressed in the Amman Message. Indeed, some blatantly violated its spirit by encouraging the demonisation of Shi'ism and the persecution of Shi'ites. In the case of Iraq, violence against Sunnis has been encouraged.

The Amman Message is an expression of the spirit of religious pluralism that defines the understanding and practice of Islam - and which is now in danger of erosion due to the narrow-mindedness of the religious establishment and the willingness of politicians to sacrifice religion for material interests. Its message and appeal for tolerance is now more vital than ever.

• The writer is an associate professor in the departments of sociology and Malay studies at the National University of Singapore.