Nahdlatul Ulama in the context of "Muhammadiyah"

Islam Nusantara or Indonesian (Islamic) model is a term used to refer to the empirical form of Islam that was developed in the Nusantara (Indonesian archipelago). This term was introduced and promoted by the Indonesian Islamic organization Nahdlatul Ulama (NU) in 2015, as a rejection of Wahhabism.

According to NU, the roots of Islam in the archipelago can be traced back to at least the 16th century, as a result of interaction, contextualization, indigenization, interpretation and vernacularization of universal Islamic values, according to socio-cultural reality of Indonesia. Islam Nusantara is defined as an interpretation of Islam that takes into account local Indonesian customs in forming its fiqh. It tends to express greater pluralism and moderation, opposition to fundamentalism, and a degree of syncretism with local traditions.

The Batak Christian Protestant Church (Indonesian: Huria Kristen Batak Protestan), abbreviated as HKBP, is an Evangelical Lutheran church among the Batak ethnic group, generally the Toba Batak people of Indonesia. This church uses an Ecumenical worship style influenced by the Dutch Reformed Church due to the influence of Dutch colonialism in Indonesia, as well as the Pietistic legacy left by the Rhenish Missionary Society when the church was founded. With a membership more than 6,500,000 (as of 2024), the church synod is the largest among the Protestant churches in Indonesia. It is one of the largest Protestant churches in Indonesia and Southeast Asia, making it the third largest religious organization in Indonesia after Nahdlatul Ulama and Muhammadiyah. Its present leader is Ephorus (bishop) Victor Tinambunan.

HKBP also has several churches abroad, such as in Europe, Singapore, Malaysia, and the United States of America.

The ideas and practices of the leaders, preachers, and movements of the Islamic revival movement known as Islamism (also referred to as Political Islam) have been criticized by non-Muslims and Muslims (often Islamic modernists and liberals).

Among those authors, scholars and leaders who have criticized Islamism, or some element of it, are Maajid Nawaz, Reza Aslan, Abdelwahab Meddeb, Muhammad Sa'id al-'Ashmawi, Khaled Abu al-Fadl, Gilles Kepel, Matthias Küntzel, Joseph E. B. Lumbard, Olivier Roy, and Indonesian Islamic group Nahdlatul Ulama.

In the context of Muslim society in Indonesia, traditionalism or traditionalist Islam refers to a religious strand which puts emphasis on preserving traditionally established local rituals and scholarship. Traditionalist Muslims refer to themselves as ahlussunnah wal-jamā'ah or aswaja. Traditionalism is often contrasted with the modernist strand, which is inspired by modernity and rationalism. Traditionalism has been the most adhered Muslim religious orientation in the history of contemporary Muslim Indonesia. The extent of traditionalism widely overlaps with the influence of a socio-religious organization Nahdlatul Ulama, the biggest Muslim organization in Indonesia. Traditionalism is also a critical element within the Muslim intellectual movement known as Islam Nusantara.