While most are aware of the association between Lucifer and Venus, most are in turn unaware of the connection between Lucifer and the Sun, with certain Egyptian gods (among others) for example. Not so much an explicit connection from or in antiquity, from the perspective of the ancients, as a re-interpretation in the context of hermeticism, in certain circles to that effect.
Our religion therefore, for the People, is the Cult of the Sun, who is our particular star of the Body of Nuit, from whom, in the strictest scientific sense, come this earth, a chilled spark of Him, and all our Light and Life. His vice-regent and representative in the animal kingdom is His cognate symbol the Phallus, representing Love and Liberty. Ra-Hoor-Khuit, like all true Gods, is therefore a Solar-Phallic deity. But we regard Him as He is in truth, eternal; the Solar-Phallic deities of the old Aeon, such as Osiris, 'Christ', Hiram, Adonis, Hercules, etc., were supposed, through our ignorance of the Cosmos, to 'die' and 'rise again'. Thus we celebrated rites of 'crucifixion' and so on, which have now become meaningless. Ra-Hoor-Khuit is the Crowned and Conquering Child. This is also a reference to the 'Crowned' and Conquering 'Child' in ourselves, our own personal God. Except ye become as little children, said 'Christ', ye shall not enter into the Kingdom of God. The Kingdom of Malkuth, the Virgin Bride, and the Child is the Dwarf-Self, the Phallic consciousness, which is the true life of Man, beyond his 'veils' of incarnation. We have to thank Freud — and especially Jung — for stating this part of the Magical Doctrine so plainly, as also for their development of the connection of the Will of this 'child' with the True or Unconscious Will, and so for clarifying our doctrine of the 'Silent Self' or Holy Guardian Angel.
-- The New Commentaries to Liber AL (The Book of Law) by Aleister Crowley
The Devil does not exist. It is a false name invented by the Black Brothers to imply a Unity in their ignorant muddle of dispersions. A devil who had unity would be a God.
"The Devil" is, historically, the God of any people that one personally dislikes. This has led to so much confusion of thought that THE BEAST 666 has preferred to let names stand as they are, and to proclaim simply that AIWAZ --- the solar-phallic-hermetic "Lucifer" is His own Holy Guardian Angel, and "The Devil" SATAN or HADIT of our particular unit of the Starry Universe. This serpent, SATAN, is not the enemy of Man, but He who made Gods of our race, knowing Good and Evil; He bade "Know Thyself!" and taught Initiation. He is "the Devil" of the Book of Thoth, and His emblem is BAPHOMET, the Androgyne who is the hieroglyph of arcane perfection. The number of His Atu is XV, which is Yod He, the Monogram of the Eternal, the Father one with the Mother, the Virgin Seed one with all-containing Space. He is therefore Life, and Love. But moreover his letter is Ayin, the Eye; he is Light, and his Zodiacal image is Capricornus, that leaping goat whose attribute is Liberty. (Note that the "Jehovah" of the Hebrews is etymologically connected with these. The classical example of such antinomy, one which has led to such disastrous misunderstandings, is that between NU and HAD, North and South, Jesus and John. The subject is too abstruse and complicated to be discussed in detail here. The student should consult the writings of Sir R. Payne Knight, General Forlong, Gerald Massey, Fabre d'Olivet; etc. etc., for the data on which these considerations are ultimately based.)
-- Magick: Liber ABA (Book 4), Part III: Magick In Theory and Practice by Aleister Crowley
Crowley unequivocally identifies his Holy Guardian Angel with Sothis (Sirius), or Set- Isis:
"Aiwaz is not a mere formula, like many Angelic names, but it is the true, most ancient name of the God of the Yezidi, and thus returns to the highest antiquity. Our work is therefore historically authentic; the rediscovery of the Sumerian tradition." I have italicized the last dozen words because they form the crux of Crowley's system, without which it is both incomprehensible and unfathom able; incomprehensible in its magical significance for the present magical revival, and unfathomable without the key supplied by the Sumerian tradition which involved the worship of Shaitan, the astronomical vehicle of which was Sirius."
Crowley, speaking for The Beast 666, declares that "Aiwaz solar-phallic-hermetic Lucifer - is His (i.e. the Beast's) own Holy Guardian Angel, and The Devil, Satan, or Hadit, of our particular unit of the Starry Universe. This serpent, Satan, is not the enemy of Man, but He who made Gods of our race, knowing Good and Evil; He bade Know Thyself and taught Initiation. He is The Devil of the Book of Thoth, and his emblem is Baphomet, the Androgyne who is the hieroglyph of arcane perfection. The number of his Atu (Key) is XV, which is Yod He, 3 the Monogram of the Eternal, the Father one which the Mother, the Virgin Seed one with all-containing Space. He is therefore Life, and Love. But moreoever his letter is Ayin, the Eye; he is Light, and his Zodiacal image is Capricornus, that leaping goat whose attribute is Liberty."
-- The Magical Revival by Kenneth Grant
The Sun is called Phæbus, Diespiter [Dispater], Apollo, Titan, Pean [Paian], Phanes, Horus, Osiris, as it is in that Oracle,
The Sun, Osyris [Osiris], Dionysus gay, Apollo, Horus, King ruling the day Who changeth times, who giveth winds and rain, The King of Stars, and the immortall flame.
He is called also Arcitenens, burning fiery, golden flaming, radiating, of a fiery hair, of a golden hair, the eye of the world, Lucifer, seeing all things, ruling all things, the creator of light, the King of Stars, the great Lord, good, fortunate, honest, pure, prudent, intelligent, wise, shining over the whole world, governing, and vivifying all bodies that have a soul, the prince of the world keeping all the Stars under himself, the light of all the Stars, darkening, burning, overcoming their vertue by his approach, yet by his light and splendor giving light and splendor to all things: in the night he is called Dionysius, but in the day Apollo, as if driving away evill things. Therefore the Athenians called him Alexicacon, and Homer Vlion, i.e. the driver away of evil things. He is also called Phæbus from his beauty and brightness, and Vulcan from his fiery violence, because the force thereof consists of many fires. He is also called the Sun, because he contains the light of all the Stars: hence he is called by the Assyrians êàãà Adad, which signifies only, and by the Hebrews ùîù Schemesch, which signifies proper.
-- Three Books of Occult Philosophy, Book II by Heinrich Cornelius Agrippa