What Javier did now was the same as what the Goddess of Bumper Harvest had done before. In order to ensure the success of the God Ceremony, Javier chose to separate his God's Kingdom, the Joy of the Wild, from the Nation of Light. The Nation of Light was the unified God's Kingdom of the Human God System where Javier had originally lived. Now, the Joy of the Wild became a self-governed kingdom, and it was moved to a place that was close to the Main Plane.
By doing that, Javier could avoid being affected by the power of beliefs of the Human God System, and he could avoid damaging his divine independence as a follower. He could also absorb and utilize the power of belief in the mortal world to the greatest extent and reduce loss.
Of course, what he did was definitely dangerous. The painful lesson of the Goddess of Bumper Harvest had happened not long ago. She had much more power and more accumulation of the church than Javier, but she had still died.