the field of social capital, and a detailed examination of the content of Nahj al-Balaghah as an exceptional selection of the sayings of Imam Ali (‘a), and using the descriptive method and content analysis tool (theme exploration or thematic analysis), we identified three main categories titled individual membership, moral membership, and social membership as subsets of the membership category. The category of individual membership is formulated within the concepts of “justice and equality”, the category of moral membership within the concepts of “knowledge and science, awareness and insight”, and the category of social membership within the concepts of “solidarity, unity and cooperation”. Thus, social capital is a central category in Nahj al-Balaghah as a precious legacy of Imam Ali (‘a), in which justice, knowledge, and cooperation find meaning within its framework, and membership is a tool on the path to sublime and improvement of individual and social affairs, which affects social capital