In The Esoteric Tradition G. de Purucker makes this statement about what Blake called the spiritual sun:
"As every scholar knows, there were a number of quasi-religious and quasi-mystical sects flourishing at about the time of the alleged beginning of the Christian era, who had pretty much the same body of ideas connected with the divine cosmic sun that the Mithraists and the Christians held. The Manichaeans were an association of mystical and in some points even esoteric thinkers, and who were widely disseminated over the Roman Empire as well as in the Hither East. They held certain beliefs linking them with the more mystical ideas of primitive Christianity, and said that the divine sun was the source of the individual christos-spirit in man, which latter is a ray of that cosmic christos. The Christian Fathers Theodoret and Cyril of Jerusalem attest this fact of Manichaean belief; and Pope Leo I called the "Great," in his Sermon XXXIV on the Epiphany (IV), stated that the Manichaeans placed the Christos of men in the [luminous substance of the invisible] sun. Such significant ideas were widely spread in the world at the time of the formation of the Christian faith and ecclesiastic system.
Of course, this view of the divine sun was not Christian only. This wonderful conception of the indwelling cosmic divinity is as old as it is universal and was the very soul of the inner meaning of ancient Greek and Latin, Persian and Mesopotamian, as well as Egyptian and Hindu religions and philosophies."
Blake assimilated the idea of a spiritual sun into his thought but more importantly, he experienced it through his own spiritual sensitivity.
Letters, To Butts, (E 722)
"Then Los appeard in all his power
In the Sun he appeard descending before My face in fierce flames in my double sight Twas outward a Sun: inward Los in his might "My hands are labourd day & night" "And Ease comes never in my sight" "My Wife has no indulgence given" "Except what comes to her from heaven" "We eat little we drink less" "This Earth breeds not our happiness" "Another Sun feeds our lifes streams" "We are not warmed with thy beams" "Thou measurest not the Time to me" "Nor yet the Space that I do see" "My Mind is not with thy light arrayd" "Thy terrors shall not make me afraid" When I had my Defiance given The Sun stood trembling in heaven The Moon that glowd remote below Became leprous & white as snow And every Soul of men on the Earth Felt affliction & sorrow & sickness & dearth Los flamd in my path & the Sun was hot With the bows of my Mind & the Arrows of Thought My bowstring fierce with Ardour breathes My arrows glow in their golden sheaves My brothers & father march before The heavens drop with human gore Now I a fourfold vision see And a fourfold vision is given to me Tis fourfold in my supreme delight And three fold in soft Beulahs night And twofold Always. May God us keep From Single vision & Newtons sleep"Blake's mastery of the dynamics of discerning the 'sun' as referring to multiple mental experiences, allowed him to people his myth with entities who moved through various transformations. Urizen and Luvah represented forces which struggled to manifest the light of consciousness in the mind of man. Each desired the position of supremacy occupied by Urthona as the connection between man and the divine. When Urizen was dormant, Luvah became ascendant. Perhaps if they worked together they could assume more power. But their plot failed and shook up the delicate mental balance necessary for smooth operation of the mind. When they became warring factions, the mind was split into two paths demanding irreconcilable goals. Urizen denied expression to the instinctual emotions of humanity. Luvah subverted the restraints which the rational mind sought to impose.
Light, Blake perceived, could not be claimed exclusively by any partial entity. Its presence must be recognized and appreciated in the functioning of disparate actions.
Four Zoas, Night I, Page 10, (E 305) "Urizen sleeps in the porch Luvah and Vala woke & flew up from the Human Heart Into the Brain; from thence upon the pillow Vala slumber'd. And Luvah siez'd the Horses of Light, & rose into the Chariot of Day" Four Zoas, Night I ,Page 21, (E 311) "But Urizen awoke & Luvah woke & thus conferrd Thou Luvah said the Prince of Light behold our sons & daughters Reposd on beds. let them sleep on. do thou alone depart Into thy wished Kingdom where in Majesty & Power We may erect a throne. deep in the North I place my lot Thou in the South listen attentive. In silent of this night I will infold the Eternal tent in clouds opake while thou Siezing the chariots of the morning. Go outfleeting ride Afar into the Zenith high bending thy furious course Southward with half the tents of men inclosd in clouds Of Tharmas & Urthona. I remaining in the porches of the brain Will lay my scepter on Jerusalem the Emanation On all her sons & on thy sons O Luvah & on mine Till dawn was wont to wake them then my trumpet sounding loud Ravishd away in night my strong command shall be obeyd For I have placd my centinels in stations each tenth man Is bought & sold & in dim night my Word shall be their law PAGE 22 Luvah replied Dictate to thy Equals. am not I The Prince of all the hosts of Men nor Equal know in Heaven If I arise into the Zenith leaving thee to watch The Emanation & her Sons the Satan & the Anak Sihon and Og. wilt thou not rebel to my laws remain In darkness building thy strong throne & in my ancient night Daring my power wilt arm my sons against me in the Atlantic My deep My night which thou assuming hast assumed my Crown I will remain as well as thou & here with hands of blood Smite this dark sleeper in his tent then try my strength with thee While thus he spoke his fires reddend oer the holy tent Urizen cast deep darkness round him silent brooding death Eternal death to Luvah. raging Luvah pourd The Lances of Urizen from chariots. round the holy tent Discord began & yells & cries shook the wide firmament"
Small Book of Designs
from Book of Urizen
"Fearless tho in pain/I travel on"
On Page 73 of William Blake's Circle of Destiny Milton O Percival states:
"Though Los's labors are too often unsuccessful, he provides such illumination as the mortal world has. He is the purveyor of its religions and its philosophies.
'If the Sun & Moon should doubt,
They'd immediately go out.' Auguries of Innocence, (E 492)
This is what happens with the Fall. Urizen, the sun, and Luvah, the moon, of the supernal world, both fall into doubt and suffer extinction of their light. To replace these darkened luminaries Los hammers the remnants of Urizen's light into a temporal sun and creates the moon of Ulro, dismal substitutes both of them for their supernal counterparts, yet they serve to light a world of darkness."