William Blake despised the classical culture of Ancient Greece and Rome, even while adapting its ideas (such as Plato’s Ideal Forms). He considered these cultures the antithesis of real art, bringers of war, destroyers of humanity. Neither did Blake appreciate the ancient (pre-Christian) British culture for its elite priestly class, the druids, to which were attributed the many stone circles and other megalithic formations, but to Blake were in the business of human sacrifice and the maintenance of a tyrannical control over the populace. Along with classical and druid culture, Blake also places Deism in the same oppressive category. Deism is somewhat of a hybrid of Christianity and Enlightenment science, where God created the world to operate under the laws of science and left it be with we humans in it. Deism does not acknowledge revelation as a means of knowledge, but instead relies on empiricism and reason for understanding truth.
So these three – classicism, the druids, and the deists – are classified as natural religion to Blake because they isolate humanity within the mundane world. Now one may argue these are not so earthbound as Blake describes them as, but were Blake around these days, and were you to engage in debate with him, you’d not likely convince him otherwise. (And that’s okay, because the aim here is to understand Blake, not change his mind.) These cultures of natural religion are Blake’s main enemies throughout his oeuvre (painted with a broad and general brush). And here the term enemies is not too strong, since Blake was vehemently opposed to them and not afraid to say so. His mythos writes them throughout as in one way or another contributing to the negating void-state known as Ulro, which is a state of tyranny upon humankind, until humans wake from their spiritual sleep.
On the upside, Blake looks to the prophets of the Old Testament, to the Gothic-Christian monks who were the intellectual and spiritual torch-bearers for England during the Dark Ages (which Blake considered a culture of wisdom and true art), and to various individuals – inspired geniuses – such as Michelangelo, Raphael, Albrecht Dürer, Shakespeare, and Jesus (on whom he has his own unorthodox views). It is such cultures and individuals which aid the restoration of a golden age.
This vision for a golden age was centred upon art. To Blake art was a spiritual practice. Considering he lived within a predominantly Christian society, his view was unorthodox: that the true Christian was an artist who exercised the imagination to restore the vision of eternity among human culture. He considered this vision to be universal, manifesting in select ways in different times, cultures, and individuals, but always originating in one divine humanity, which he called Poetic Genius. Humans who strived with their creative imagination could tap into this genius and reintegrate their being into eternity, as eternal artists of the imagination, thereby bringing creations of eternal forms, of art and science and wisdom, into the world, into earthly culture. Such a culture could restore on earth the completeness of human nature; the individual living as a balanced, complete human being; a harmonious integration of what Blake calls the Four Zoas in his mythos: Reason (Urizen), Imagination (Urthona), Sensuality (Tharmas), and Emotion/Energy (Luvah).
Blake saw this human connection (individually and culturally) with eternity, with Poetic Genius – the origin and ‘blueprint’ for human wholeness – as the normal state for humanity, from which many people, in his time, had fallen from. This normal, eternal state was no static paradise, but a continual striving in the work of the creative imagination; to discover, experience, explore, and express eternal art, science, and culture based upon wisdom.