The third is moral philosophy and selected streams of theological ethics. More adequate moral frameworks is not the chief goal, however. They mean little apart from moral formation itself, in view of an altered relationship to Earth. While there is nothing magic in the choice of these three, I do think they are particularly suggestive as sources for an ecumenical earth ethic. There have always been Christian communities as communities of renunciation and annunciation.
Monasticism is one obvious strand, but ascetic Protestant communities show similar traits.
A close look uncovers both the life of renunciation and a simultaneous effort to embody harmony with nature as manifest in clothing and diet, agricultural and healing practices, art and architecture. There it is renewed in contemplative and sacramental practices. Life is a gift of God and the medium of grace. Far more than a gathering of God and humankind, sacramental communion is ritually enacted as the hymn of the universe itself. Its great acts are acts of the cosmic drama of creation itself, its story one that proclaims a God beyond dimensions we can know yet as near as the grain and the grape, the water and the oil.