As urbanization accelerates, the interaction between religious sites and ecological space development warrants further exploration, particularly in Thailand, where inadequate infrastructure impedes smart city advancement. This research examines religious sites surrounding Khon Kaen Lake in Khon Kaen City, specifically the Pun Tao Kongma shrine, and the Nongwaeng, That, and Klang temples as case studies. Employing qualitative methods, including participant observation and in-depth interviews, the research investigates how these sites contribute to urban ecological space creation through the perspectives of nudge theory. Findings reveal that religious ecological perspectives, such as the Buddhist concept of Sappaya 7 and Thai-Chinese beliefs in the interdependence of humans and nature, underscore the significance of ecological spaces in daily life. These shared eco-conscious values are increasingly relevant amid rising urban air pollution and can be leveraged within religious spaces to enhance their nudging effect on public behavior. Furthermore, religious sites, acting as urban nodes, can accumulate cultural and social capital through rituals, events, and spatial practices. This synergistic potential supports both the development of urban ecological environments and the overall resilience of the city, aligning with an urban “sharing” model that integrates ecological, economic, and sociocultural functions. The proposed vision includes reducing permanent structures in favor of multifunctional shared or mobile buildings, thereby maximizing public access to urban green spaces. Ultimately, this research suggests that embedding shared religious ecological perspectives, architecture, and cultural capital into urban planning can lay a foundation for sustainable smart city development in Thailand amid global urbanization challenges.