"One aspect of Stoic writing that seems to deter many modern readers and rather clashes with the scientific world-view of CBT is the presence of 'God'. However, it should be remembered that the meaning of this word in modern society is laden with Christian theological connotations that are alien to ancient Stoic writers."
"Certain Stoics appear to have been willing to contemplate agnosticism or atheism as consistent with their philosophy. As Marcus Aurelius repeats to himself, whether the universe is 'God or atoms', either way the basic precepts of Stoicism still stand firm. However, most Stoics do refer repeatedly, and often passionately, to one's relationship with God. The God of the Stoics is a philosopher's god, though, and not merely a mythic creation. He is synonymous with fate itself, or the whole of nature, and, therefore, 'belief in God' is more a question of language or perspective than a metaphysical hyposthesis. Hence, Zeno reputedly said, 'it matters not whether you call it Providence or nature' (Lipsius, 2006, p.65). Seeing the universe itself as divine is the rational mysticism of great scientists like Einstein, a question of one's attitude toward life, and not a question of believing that something exists. Note, for instance, that for a pantheist, the question 'Does god exist?' would simply be another way of asking 'Does the universe exist?', which is, arguably, a nonsensical question. The Stoic God is not really a 'thing', a mythical superhuman being, to be believed in or not, like a glorified unicorn. Rather, it is a way of looking at the world, conceiving the universe itself, in its absolute entirety, as if it were godlike, as being divine, mystical, and sacred in its totality. The references to 'God' in Stoicism, to put it bluntly, could probably be replaced by the word 'Nature' or 'the Universe' without much loss of meaning, as Zeno himself says, and doing so would probably render things much easier to digest for modern CBT practitioners."
I loved this quote, as it so succinctly and brilliantly illustrates many important points about Stoicism and about conceptions of the divine in traditions other than (and usually predating) the now more familiar monotheistic traditions that arose in the East yet now dominate the religious discourse of the West. In a sense, the Abrahamic monotheist faiths have "poisoned the well" for any kind of rational discussion of the nature of religion or spirituality. Many people in the modern West, raised with the now-dominant background of Judaeo-Christian-Islamic traditions in the background, and having rejected those faiths, construct intensely flawed arguments about and against religion or spirituality based on monotheism - as if in their eyes, monotheism = religion. So I hear tired old ideas like "Well, all religions claim to be the One True Way, and persecute those who disagree, right?" Nope - not by a long shot - not even a significant minority, for the majority of human history - but yes, Christianity, Islam, and even Judaism are all guilty of this to some extent. To many ancient pagans, claiming that the spiritual or divine didn't exist was clearly insane - everyone had personal experience of the divine in the world, after all, and the only way to claim it didn't exist would be to make the insane claim that the universe didn't exist either. I get very frustrated at the level of ignorance and arrogance from those who claim to be "free thinkers" and "atheists," many of whom simply assume that they are right, and any theist/religious/spiritual person is automatically wrong.
Even so, the author's point is well-taken - you can actually leave religion out of Stoicism, and get the same results, because its "religion" is simply the belief in the existence of reality and the application of reason as the best method of understanding and dealing with that reality.