Jacolliot's Occult science in India was written during the 1860s and published 1875 (English translation 1884). Jacolliot was searching for the "Indian roots of western occultism" and makes reference to an otherwise unknown Sanskrit text he calls Agrouchada-Parikchai, which is apparently Jacolliot's personal invention, a "pastiche" of elements taken from Upanishads, Dharmashastras and "a bit of Freemasonry". Jacolliot also expounds his belief in a lost Pacific continent, and was quoted on this by Helena Blavatsky in Isis Unveiled in support of her own Lemuria.
In Jacolliot's book La Bible dans l'Inde, Vie de Iezeus Christna (1869) (The Bible in India, or the Life of Iezeus Christna), he compares the accounts of the life of Bhagavan Krishna with that of Jesus Christ in the Gospels and concludes that it could not have been a coincidence, so similar are the stories in so many details in his opinion. He concludes that the account in the Gospels is a myth based on the mythology of ancient India. Jacolliot does not claim that Jesus was in India as some have claimed. "Christna" is his way of spelling "Krishna" and he wrote that Krishna's disciples gave him the name "Iezeus" which means "pure essence" in Sanskrit.
Jacolliot was successfully sued for defamation by Father Honoré Laval ss.cc, and ordered by the Supreme Court of the State of the Protectorate of he Society Islands to pay 15,000 francs in damages. It ordered the suppression of those portions of the pamphlet "La verité sur Tahiti" deemed defamatory, and further ordered that the judgement be printed in the official journal of the Protectorate in French, English, and Tahitian, as well as, in three newspapers of the French colonies, three journals of Paris, and four gazettes of provinces of Laval's choosing.
He has been described as a prolific writer for his time. During his time in India he collected Sanskrit myths, which he popularized later starting in his Histoire des Vierges. Les Peuples et les continents disparus (1874). Among other things, he claimed that Hindu-writings (or unspecified "Sanskrit tablets") would tell the story of a sunken land called Rutas in the Indian Ocean. However, he relocated this lost continent to the Pacific Ocean and linked it to the Atlantis-myth. Furthermore, his 'discovery' of Rutas is somehow similar to the origin of the Mu-Story.
La Bible dans l'Inde, ou la Vie de Iezeus Christna (The Bible in India or The life of Iezeus Christna) (1869)
Les Fils de Dieu (God's Sons) (1873)
Christna et le Christ (Christna and Christ) (1874)
Histoire des Vierges. Les Peuples et les continents disparus (History of the Virgins. Vanished People and Continents) (1874)
La Genèse de l'Humanité. Fétichisme, polythéisme, monothéisme (Genesis of Mankind. Fetichism, polytheism, monotheism) (1875)
Le Spiritisme dans le monde, L'initiation et les sciences occultes dans l'Inde et chez tous les peuples de l'antiquité, Paris: Lacroix, 1875, 1879, reprint Geneve, Paris: Slatkine 1981.
translated into English as Occult science in India and among the ancients, with an account of their mystic initiations, and the history of spiritism, New York: Lovell/ London 1884, reprinted 1901, 1919; New Hyde Park, N.Y.: University Books 1971.
Les Traditions Indo-européennes et Africaines (Indo-European and African Traditions) (1876)
Pariah dans l'Humanité (The Outcasts in the History of Mankind) (1876)
