Final answer:
Sufi mystics and spiritual teachers significantly influenced the spread of Sunni Islam in Indonesia by integrating Islamic practices with local traditions and appealing to the common populace.
Step-by-step explanation:
The Sufi mystics and spiritual teachers were influential in spreading the Islamic tradition of Sunni Muslims in Indonesia. Sufis are known for their ascetic practices, meditation, and use of music, poetry, and dance to experience the divine presence, which appealed to the general population beyond scholarly theological debates. The Sufi orders, which formed around a revered leader and religious teacher, played a crucial role as missionaries, blending Islam with local traditions and fostering the conversion of non-merchants to Islam in Southeast Asia, including Indonesia. Their amenable approach allowed for a seamless integration of Islam into local religious practices, aiding its spread and acceptance across diverse regions.