All of nature is symbolic and I believe the ancients understood this; so what might appear only as nature or sun worship to a modern mind is ontologically more deeper. Tradition, especially ancient paganism, takes its symbols and correspondences from nature, but that doesn't make it naturalism. Even in (traditional) Christianity, after Europeanization, the liturgical year was built around the natural cycles. It is not so much a case of borrowing than about 'traditionalization'. Early Christianity was nihilistic towards this cyclical understanding and the linear understanding of history is completely anti-traditional. This symbolic understanding of nature completely eludes the modern mind that has flattened and secularized the cosmos and makes it impossible to understand the traditional understanding of natural phenomena. This applies to modern pagan naturalism also.