I think it is useful to conceive how the universe has both the quality of dualityand oneness at the same time. I view it in this way: it is implicit that there is a duality between heaven and hell, body and spirit, earth and sky, male and female, but this duality is contained in an overarching oneness. The overarching oneness can be defined in this way; The Lord is the one source of life and is love itself. Even though heaven and hell are opposing forces, there is still oneness, because in the higher sense heaven is life, and hell is anti-life, or spiritual death. That is different than each having its own source; if that were the case it would be a true duality. But the Lord is the only source of life, for heaven and hell; hell is an inversion of his life; hell’s reception of his life is in a perverse form. The duality is real, but it’s effects only manifest on the natural plane. In the natural plane it is possible to be in emotional/spiritual duplicity, but on the spiritual realm of heaven and hell everyone has a singular love, whether it be love or hate for the Lord. Either way everything that exists is defined by the quality of its relationship to the One – the Lord.