Microbes make us human. From digestion, immunity, and brain development, to our neurological capacity for discipline, wisdom, and compassion, being human depends on the presence of our microbial inhabitants or our “microbiome.” In turn natural scientists, philosophers and anthropologists aren’t sure where microbes end and we begin. They say humans are microbial, that we’re multispecies. The shifts about being human bear on Christianity, which rises and falls on the claim that God became fully human. If humans are microbial, is God also microbial?

The microbiome causes good trouble for theology. For example, ecotheologians rightly blame the image of God trope for the psychological wedge it places between humans and the rest of creation. Symbiotic Grace uses new microbial truths to disrupt humanity's exclusive claim to the imago dei. It shows Christians how humanity's entangled dependence on manifold species reflects a triune God who is also symbiotic. Thus we cannot image God alone.
Practically, many North American churches already do ecological things: parish gardens, recycling, etc. They preach “care of the earth" or stewardship. Their eco-practices are about Creation. But most churches haven’t considered how earthcare interacts with how they see Jesus and themselves. Symbiotic Grace takes ecological stewardship, a side issue for many, and integrates it into the heart of salvation.

I am writing the first systematic theology of the microbiome, Symbiotic Grace: Holobiont Theology in the Age of the Microbe. It investigates how the microbial nature of God and humanity offers new ways for churches to address historic environmental, racial, and public health failures in the North American Church while developing a “citizen theology” method akin to citizen science, wherein churches become integral participants in the theological academy’s task.