Theravada Buddhism is more than just a philosophy, more than a tradition of the book, of monasticism, or meditation. As any visitor to Sri Lanka or Southeast Asia can observe, the Buddhism practiced in this region is far from austere, and in Thailand especially, it is eclectic. The guiding questions of this dissertation ask, what can a material, rather than solely textual, investigation reveal about Thai Buddhism? What can we learn from studying objects, and their associated networks? Following a New Materialist approach, this dissertation does two things: (1) it celebrates the eclectic and rich material world of Thai Buddhism by using Wat Arun as a case study to discuss the practice of contemporary Thai religiosity; and (2) this dissertation makes a theoretical intervention in the New Materialist human-and-nonhuman paradigm by calling for the acknowledgment of a “Third Agent”, adapted from what the Thai regard as saksit, that which is worthy of worship and reverence. An acknowledgment of the Third Agent also leads to an acknowledgment of what I call “invisibles”, those agents (human or nonhuman) on the periphery that are influential in the make up of Thai Buddhism. The dissertation’s four content chapters investigate four significant objects/elements associated with Wat Arun, and also outlines four sub-arguments related to the theoretical intervention. Chapter (1) introduces the Third Agent through the rituals related to a statue of King Taksin (r.1767-1782), considered the founder of Wat Arun. Chapter (2) focuses on the ceramics adorning the main architectural tower (prang) and the controversies post-2011-2017 renovation, demonstrating that belief in a Third Agent is inconsequential. Chapter (3) discusses amulets, which are important in maintaining relations, especially as meta-Third Agents. Chapter (4)’s analysis of water reveals the “invisibles” that have shaped Wat Arun. In short, this dissertation argues that an investigation of material things and their related networks offer a window into how Buddhists comport themselves with-, among-, to-, and for other Buddhists, material things, and immaterial things or Third Agents, and that by paying attention to the wider network and relationships themselves, we can uncover treasures among that which is dismissed as trash.