The Tang monk Tripitaka (Tang Sanzang, 唐三藏; a.k.a. Xuanzang) is depicted in Journey to the West (Xiyouji, 西遊記, 1592) as the earthly reincarnation of Master Golden Cicada (Jinchan zi, 金蟬子) (fig. 1), the Buddha’s fictional second disciple. This deity is banished to live out ten pious lives in China until the time comes for him to build merit as the scripture pilgrim, thereby gaining reentry into paradise. His crime of not paying attention to the Buddha’s lectures and subsequent exile to the mortal realm is encapsulated in part of a poem from chapter twelve:
Gold Cicada was his former divine name.
As heedless he was of the Buddha’s talk,
He had to suffer in this world of dust,
To fall in the net by being born a man
[…] (Wu & Yu, 2012, vol. 1, p. 275).
I. Similarities to Western philosophy
McEvilley‘s (2002) The Shape of Ancient Thought reveals Tripitaka’s story is preceded by beliefs from Greek Orphic and ultimately Egyptian philosophy. For example, Empedocles (5th-c. BCE) wrote of gods being exiled from heaven for ten thousand years for the crime of murder or lying under oath. The fallen deity is believed to reincarnate into every creature of land, air, and sea (fig.3), and when their long punishment is up, they are reborn in their last life as a person of high culture, such as royalty, religious leaders, and scholars. They then return to their former heavenly station upon death (McEvilley, 2002, p. 106).  Plato (5th to 4th-c. BCE) specifically mentions the god undergoing ten reincarnations interspersed with thousand-year-long periods of afterlife reward or punishment (McEvilley, 2002, p. 108).  The multiples of ten mentioned here fascinate me as they relate to the number of Tripitaka’s incarnations.
Fig. 3 – A symbolic painting showing the course of life, death, and reincarnation (larger version). Artist unknown.
McEvilley (2002) continues by tracing these and related Greek and Indian beliefs to the Egyptian Book of the Dead:
The deceased must somehow be regarded as a king or prince before he is eligible to “get thee back to the heights of heaven.” Thus Ani declares, “I am crowned like unto the king of the gods, and I shall not die a second time in the underworld.” Again, the prayer is made, “May Osiris, the scribe Ani, be a prince … and may the meat offerings and the drink offerings of Osiris Ani, triumphant, be apportioned unto him.” “I am crowned,” Ani claims, “I am become a shining one, I am mighty, I am become holy among the gods.” “I am the prince of eternity.” “May it be granted that I pass on among the holy princes,” Ani prays, and he is reassured: “The god Tmu hath decreed that [Ani’s] course shall be among the holy princes.” “Horus,” the Book of the Dead says, “was like unto a prince of the sacred bark, and the throne of his father was given unto him.”
Something very like the doctrine of Empedocles is suggested, and possibly related to it as forerunner. The ba, which was once a god among the other gods, descends to earth, that is, into a body, in order to right some wrong it has done in the past; either it descended as a pharaoh or it has somehow been processed through nature for long ages until it has purified itself sufficiently to be reborn as a pharaoh; after its purification it is ready to return to the company of the gods in heaven, and this is signified by the status as pharaoh. Empedocles said the final incarnation was as a prince, a poet, or a healer. Plato said the last reincarnation was as a philosopher—but he meant philosophers to be kings. They both may be echoing an Egyptian idea either that gods are incarnated only as pharaohs or that the last incarnation is as a pharaoh. A parallel is found in the Hindu caste system, in the idea that only brahmans can attain moksa—that is, “become Osiris”; the soul must reincarnate upward through the castes before it is in position to get off the wheel.
The nature of the primal crime or ancient wrong which the soul “descended on to the earth” to set right is not clearly stated, as it is not in the Greek versions of the myth, where it is either left undefined or ambiguously declared to be either perjury or bloodshed. The Egyptian texts dwell repeatedly on this subject, but with an ambiguity not unlike that of the Greek texts. Various clues in the Greek tradition indicate that the crime which the Orphic was attempting to expiate was either the ancient war of the Titans against the gods, for which they were exiled from heaven and imprisoned in Tartarus, or their rending and devouring of Dionysus Zagreus, or both. (In the Greek tradition, as West says, “The Titans are by definition the banished gods, the gods who have gone out of this world.”) The Egyptian texts may foreshadow the Greek myth of the Titans when they refer to a primal rebellion of one group of gods against another. “O ye gods of the underworld,” Osiris Ani says, “who set yourselves up against me, and who resist the mighty ones …” Again, he says:
Hail, Thoth! What is it that hath happened unto the holy children of Nut? They have done battle, they have upheld strife, they have done evil, they have created the fiends, they have made slaughter, they have caused trouble; in truth, in all their doings the mighty have worked against the weak …I am not one of those who work iniquity in their secret places; let not evil happen unto me.
The children of Nut include Osiris, Horus, Set, Isis, and Nephthys. When Ani claimed “before Isis I was,” he was dissociating himself from this contentious generation of deities in which the primal murder of Osiris by Set occurred, and claiming to have been one among the earlier generation, the “gods of the first time.” But there are also suggestions that the crime might be Set’s dismemberment of Osiris, whom Ani, in his role as Horus, avenger of his father, has to reconstitute to make reparation. Ani, in other words, might be expiating either or both of the Egyptian versions of the crimes of the Titans, and part of his strategy in doing so is to claim that he belongs to the earlier generation of gods (pp.131-133). 
So the crime of murderous rebellion or bearing a false oath became inattentiveness to the Buddha’s teachings in Journey to the West. And the gods of ancient Greece and Egypt became a son of Buddha punished to ten reincarnations as a mortal, his last one as a holy monk. This final point mirrors the concept of the last incarnation being a grand one as a king or holy person.
How these beliefs or related proto-beliefs came to China is unknown to me. If pressed, I would venture it involved some Buddhist text containing an ancient Indian arm of this philosophy.
II. Connection to the other pilgrims
I can’t pass up the opportunity to mention how this also relates to the other pilgrims, who are portrayed as former gods exiled from heaven for some offense. In place of several rounds of reincarnation, they are (among other punishments) forced to serve as Tripitaka’s guardians, protecting him from leagues of demons wanting to jump ahead in the cosmic hierarchy by eating the the monk’s flesh and gaining immortality. Marshal Tianpeng (Zhu Bajie) is banished for drunkenly forcing himself on the Moon goddess and reborn as a grotesque pig spirit (Wu & Yu, 2012, p. 212) (fig. 2). The Curtain-Raising General (Sha Wujing) is banished for breaking a treasure cup at a heavenly banquet and reborn as a monstrous water spirit plagued by a magic sword that stabs at him weekly (Wu & Yu, 2012, p. 209-210).  The dragon prince, son of the Western Sea Dragon King Aorun, is banished for burning a heavenly pearl (Wu & Yu, 2012, p. 213-214), but in place of execution, he agrees to transform into a dragon horse (a kind of rebirth) and serve as Tripitaka’s mount (Wu & Yu, 2012, p. 328). And even Sun Wukong is banished for his rebellion (the divine crime mentioned above) and punished to imprisonment under Five Elements Mountain. It’s interesting to note that one scholar suggests this punishment represents a symbolic death, leading to his eventual reincarnation (see Shao, 1997). (I’d like to add Sun’s additional punishment of eating a hellish diet of molten copper and hot iron balls speaks to a transitional period of afterlife punishment.) And once the pilgrims complete their penance (i.e. the journey), all are welcomed back into heaven, in this case the Buddha’s paradise.
Fig. 2 – A Taiwanese stamp featuring Zhu Bajie and the moon goddess.
Below I present a PDF of McEvilley (2002). I converted it from an EPUB, meaning the page count is not the same as the physical edition cited above. I originally intended to just post chapter four, but I was afraid of breaking any internal links, so I instead posted the entire book. This is a very fascinating read. Just know that it is extremely dense and can be hard to follow at times if you lack deep knowledge in Western philosophical history and belief.
This has been uploaded for educational purposes. No malicious copyright infringement is intended. Please support the official release.
1. This appears on page 206 of the PDF.
2. See pages 209-210 in the PDF.
3. See pages 247-249 in the PDF.
4) It could be argued that Zhu and Sha do not reincarnate but simply take on monstrous forms upon being banished to earth because they still retain their memories, weapons, and magical skills. But maybe, as immortals, they are able to affect their own rebirth by directing the final destination of their primal spirit, thereby bypassing the normal mode of reincarnation that results in the loss of memory. An example of this is the rogue immortal Huaguang (華光) from Journey to the South (Nanyouji, 南遊記, 17th-c.), who is reborn several times and still has memories of his past and access to his holy weapons.
McEvilley, T. (2002). The Shape of Ancient Thought: Comparative Studies in Greek and Indian Philosophies. New York: Allworth.
Shao, P. (1997). Monkey and Chinese Scriptural Tradition: A Rereading of the Novel Xiyouji (UMI No. 9818173) [Doctoral dissertation, Washington University]. Available from ProQuest Dissertations and Theses database.
Wu, C., & Yu, A. C. (2012). The Journey to the West (Vol. 1). Chicago: University of Chicago Press.