This research uses literature study and field study methods in a qualitative form with an interview approach. The intention is to explore the GUSJIGANG Philosophy to support faith communication and build brotherhood with other identities.

The term Gusjigang has long been recognized by the people of Kudus who live in the west or around the area of the Menara Mosque and the Tomb of Sunan Kudus. Gusjigang is a form of local culture, which is ingrained in the people of Kudus. It is said that the originator was Sayyid Dja'far Shodiq (Sunan Kudus). The people of Kudus want to preserve the traditions that have been passed down from generation to generation. Gusjigang itself is an acronym for bagus, ngaji and dagang. Gus - good - relates to positive attitudes in individual ethics, such as compassion, tepo seliro (tolerance), mutual help, courtesy, and refinement as a reflection of understanding of Islam. Ji comes from the word ngaji, meaning a sincere and happy attitude to increase knowledge, and gang comes from the word dagang, which means earning a living through trading or entrepreneurship. These three values are interrelated within the scope of principles: (1) divinity, (2) civilization, and (3) welfare to support life together.

In this research, the author uses the theoretical framework of Ali Asghar Engineer's Liberation Theology (1939-2013) in realizing universal brotherhood, equality, social justice and interfaith dialogue. Ali Asghar's Liberation Theology seeks to share and apply his ideas to fight oppression in order to give birth to human freedom and the spirit of social solidarity and be able to face challenges in the midst of global life. The basic idea of Ali Asghar's liberation theology is motivated by the context of religious plurality that occurs in India. Ali Asghar seeks to reformulate the meaning of religion in human life. For Ali Asghar, theology needs to be addressed because it often only becomes the status quo, not contributing to the progress of thinking. Islamic theology only talks about God at a metaphysical level, such as the oneness of God, God's omnipotence, God's attributes, destiny and eschatological issues. Religion actually has two faces, it can be a complaint for the oppressed or a weapon for revolution against the status quo. Ali Asghar's vision is: (1) reason and revelation must support each other, (2) religious plurality and diversity is a necessity, (3) the character of diversity is reflected in a brotherly attitude towards those who are oppressed.

In relation to the context of Islam in Indonesia and its relevance for today, the author relates it to the theory of the Trilogy of Ukhuwah (ukhuwah islamiyyah, ukhuwah wathaniyyah, ukhuwah bashariah) and the Document of Human Fraternity. The research led to the finding that the GUSJIGANG philosophy has an influence in building, maintaining brotherhood and supporting faith communication.