“Druids – A sacerdotal caste which flourished in Britain and Gaul. They were Initiates who admitted females into their sacred order, and initiated them into the mysteries of their religion. They never entrusted their sacred verses and scriptures to writing, but, like the Brahmins of old, committed them to memory; a feat which, according to the statement of Caesar, took twenty years to accomplish. Like the Parsis they had no images or statues of their gods. The Celtic religion considered it blasphemy to represent any god, even of a minor character under a human figure. It would have been well if the Greek and Roman Christians had learnt this lesson from the “pagan” Druids. The three chief commandments of their religion were: – “Obedience to divine laws; concern for the welfare of mankind; suffering with fortitude all the evils of life.”
— H.P. Blavatsky, Theosophical Glossary, p. 105
“The mystery veiling the origin and the religion of the Druids, is as great as that of their supposed fanes is to the modern Symbologist, but not to the initiated Occultists. Their priests were the descendants of the last Atlanteans, and what is known of them is sufficient to allow the inference that they were eastern priests akin to the Chaldeans and Indians, though little more. It may be inferred that they symbolized their deity as the Hindus do their Vishnu, as the Egyptians did their Mystery God, and as the builders of the Ohio Great-Serpent mound worshipped theirs – namely under the form of the “mighty Serpent,” the emblem of the eternal deity TIME (the Hindu Kala). Pliny called them the “Magi of the Gauls and Britons.” But they were more than that. The author of “Indian Antiquities” finds much affinity between the Druids and the Brahmins of India. Dr. Borlase points to a close analogy between them and the Magi of Persia; others will see an identity between them and the Orphic priesthood of Thrace: simply because they were connected, in their esoteric teachings, with the universal Wisdom Religion, and thus presented affinities with the exoteric worship of all.
“Like the Hindus, the Greeks and Romans (we speak of the Initiates), the Chaldees and the Egyptians, the Druids believed in the doctrine of a succession of worlds, as also in that of seven “creations” (of new continents) and transformations of the face of the earth, and in a seven-fold night and day for each earth or globe (See “Esoteric Buddhism”). Wherever the Serpent with the egg is found, there this tenet was surely present. Their Dracontia are a proof of it. This belief was so universal that, if we seek for it in the esotericism of various religions, we shall discover it in all. We shall find it among the Aryan Hindus and Mazdeans, the Greeks, the Latins, and even among the old Jews and early Christians, whose modern stocks hardly comprehend now that which they read in their Scriptures. …
“The Druids understood the meaning of the Sun in Taurus, therefore, when, while all the fires were extinguished on the 1st of November, their sacred and inextinguishable fires alone remained to illumine the horizon, like those of the Magi and the modern Zoroastrians. And like the early Fifth Race and later Chaldees, the Greeks, and again like the Christians, who do the same to this day, without suspecting the real meaning, they greeted the Morning Star – the beautiful Venus-Lucifer. Strabo speaks of an island near to Britannia, “where Ceres and Persephone were worshipped with the same rites as in Samothrace (lib. iv.) and this island was “Sacred Ierna,” where a perpetual fire was lit. The Druids believed in the rebirth of man, not as Lucian explains: “that the same spirit shall animate a new body, not here, but in a different world,” but in a series of re-incarnations in this same world; for as Diodorus says, they declared that the souls of men, after determinate periods, would pass into other bodies.*
“These tenets came to the Fifth Race Aryans from their predecessors of the Fourth Race, the Atlanteans. They had piously preserved the teachings, which told them how their parent Root-Race, becoming with every generation more arrogant, owing to the acquisition of super-human powers, had been gradually gliding toward its end. Those records reminded them of the giant intellect of the preceding races as well as of their giant size. One finds the repetition of those records in every age of history, in almost every old fragment which has descended to us from antiquity.”
* “There was a time when the whole world, the totality of mankind, had one religion, and when they were of “one lip.” “All the religions of the Earth were at first One and emanated from one centre,” says Faber very truly.”
— H.P. Blavatsky, The Secret Doctrine, Vol. 2 (Anthropogenesis) pp. 756, 759-760