After being released from his mountain prison in chapter fourteen, Sun Wukong effortlessly kills a tiger with his iron staff and uses a magic hair-turned-knife to skin the beast. He cuts a large square from the fur and uses half to create a loincloth to cover his naked body (Wu & Yu, 2012, vol. 1, pp. 309-310). This tiger skin clothing is a highly recognizable element of Monkey’s iconography (fig. 1). But did you know it has a connection to the Wrathful Destroyers of Obstacles (Sanskrit: krodha-vighnantaka),  a class of supreme guardian deities in Indo-Tibetan Esoteric Buddhism?
Before I continue, some historical background is needed. Esoteric Buddhism first developed in India as an offshoot of Mahayana Buddhism during the sixth-century CE. Wrathful Destroyers of Obstacles (WDO, hereafter) appear in three recognized iconographic phases stretching from the sixth to the twelfth-century. The first and longest phase (6th-12th cent.) depicts the WDO as a dwarfish attendant to a full-size Bodhisattva.  He serves as the personification of his master’s wisdom and abilities. The second phase (8th-10 cent.) represents the WDO as an independent deity with his own attendants. He serves as the personification of the attributes of the five esoteric Buddhas. The third phase (late 10th-12th cent.) represents the WDO as the equal of Buddhas (Linrothe, 1999, pp. 11-14).
Wrathful Destroyers of Obstacles are often depicted as fierce, multi-armed figures bearing weapons and, most importantly, wearing tiger skin loincloths (Sanskrit: Vyaghracarma-nivasana). For example, the Manjusrimulakalpa, an eighth-century esoteric text, dictates the prescribed iconography of Manjusri’s WDO guardian Yamantaka (“the Destroyer of Yama, god of death”):
Six faces, six arms and feet/Black in color, with a big belly / Bearing a skull, his hair flaring out in anger / A tiger skin wrapped around the hips / Holding all kinds of implements and weapons” (fig. 2) (Linrothe, 1999, p. 66). (emphasis mine)
The Hevajra Tantra, another eighth-century esoteric work, ties tiger skin clothing to Yogin practices. The text instructs them on how to adorn and dress themselves for worshipping the WDO Heruka:
The yogin must wear the sacred ear-rings, and the circlet on his head; on his wrists the bracelets, and the girdle round his waist, rings around his ankles, bangles round his arms; he wears the bone-necklace and for his dress a tiger-skin… (Linrothe, 1999, p. 250). (emphasis mine)
Furthermore, it describes how each of the ritual adornments and implements used in the ceremony represents each of the five esoteric Buddhas, as well as other religio-philosophical elements:
Aksobhya is symbolized by the circlet, Amitabha by the ear-rings, Ratnesa by the necklace, and Vairocana (by the rings) upon the wrists. Amogha is symbolized by the girdle. Wisdom by the khatvanga [staff] and Means by the drum, while the yogin represents the Wrathful One himself [Heruka]. Song symbolizes mantra, dance symbolizes meditation, and so singing and dancing the yogin always acts (Linrothe, 1999, p. 251).
The scholar Van Kooij comments, “Heruka is more or less a deified hypostasis of the … yogin himself” (Linrothe, 1999, p. 251). This suggests the WDO are dressed according to what is worn by the very Yogin ascetics who worship them. But I would like to take this one step further. It is important to note that many of these elements, such as the earrings, bracelets, arm bangles, bone necklace, tiger skin dress, khatvanga staff, drum, and dancing, are all attributes of the Hindu God Shiva. He is considered the yogin par excellence, as well as a wrathful deity in his own right (Elgood, 1999, pp. 44-54). I therefore suggest the practice of wearing tiger skin was just one of many elements that esoteric Buddhism borrowed from Hindu asceticism.
Fig. 1 – (Left) A modern depiction of Sun Wukong (by the author) (larger version). Fig. 2 – (Center) A 13th-century Japanese depiction of the Wrathful Destroyer of Obstacles Yamantaka (larger version). Fig. 3 – (Right) A modern depiction of the Hindu god Shiva (larger version).
Shiva is often depicted as wearing a tiger skin and/or using it as a meditation mat (Skt: Asana) (fig. 3). This skin has two interpretations: 1) it represents his power over nature; 2) it represents him killing the personified “tiger of desire” (Elgood, 1999, p. 52; Beer, 2003, p. 65). When viewed from a Buddhist context, it seems only natural that Buddhist ascetics and deities would use the skin to represent the cessation of desire. It should also be noted that tigers and their skin were symbols of strength in ancient India. For instance, the great Hindu epic the Mahabharata (circa 4th-cent. BCE), describes the martial feats or attributes of many powerful warriors and kings as being tiger-like (Śarmā, 1988, p. 66). In addition, during the royal consecration ceremony (Skt: Rajasuya), newly appointed Vedic kings would step on a tiger skin to gain the animal’s strength (MacDonell & Keith, 1995, p. 337). I therefore suggest the WDO tiger skin loincloth serves a secondary function as a symbol of the WDOs spiritual or physical strength.
There are numerous classes of Buddhist deities that share similarities with the WDO, such as having a wrathful appearance and serving a protective function, but do not rank as high in the esoteric pantheon. These include the Heavenly Kings (天王, tianwang; Skt: Lokapala) (fig. 4), who protect righteous kingdoms and monasteries; Gate Guardians (門神, Menshen; Skt: Dvarapala), who protect the doorways of monasteries and temples; the Protector of Fields (Skt: Ksetrapala), who protect plots of land; the Guardians of the Directions (Skt: Dikpala), former Hindu gods who protect the eight directions; and the Dharma Protectors (Skt: Dharmapala), who protect the Buddha’s teachings (Linrothe, 1999, pp. 20-22).
Wrathful Destroyers of Obstacles stand high above these other guardians because they are charged “with the destruction of barriers which prevent the experience of enlightenment” (Linrothe, 1999, p. 25). These barriers include external threats like manifested demons and internal threats like demon-caused mental and bodily illness, the “three poisons”, and karmic debt (Linrothe, 1999, pp. 24-25).  And they have the power to subdue even supreme devas. For example, the Compendium of the Truth of All Buddhas (Skt: Savra-tathagata-tattva-samgraha, late 7th-cent.) tells of the Cosmic Buddha Mahavairocana ordering the WDO Trailokyavijaya (the wrathful form of Vajrapani) to conquer Mahesvara (a.k.a., Shiva), king of the gods and master of the three realms. After being subdued, the fallen god asks the Buddha: “[H]ow it can be that Vajrapani, whom in anger [I]…called a mere Yaksa, can be so strong, stronger even than the Tathagata as Lord of the Trikaya[?]” (Linrothe, 1999, p. 26). 
Fig. 4 – (Left) Statues of the Four Heavenly Kings located in Beihai Park, Beijing, China (larger version). Fig. 5 – (Right) A modern toy depicting Monkey’s fearsome three-headed, six-armed form (larger version).
Many of Sun Wukong’s attributes and abilities align with those mentioned above, I would therefore like to argue that he is a Wrathful Destroyer of Obstacles. First, he wears the tiger skin loincloth, which ties him to the same spiritual tradition represented by WDOs and Yogin ascetics. Second, he has a wrathful appearance (Skt: krodha). During his war with heaven, he takes on a fearsome form with three heads and six arms and multiplies his iron staff to defeat wave after wave of celestial opponents (fig. 5) (Wu & Yu, 2012, vol. 1, pp. 157 and 191). This is similar to the multiple heads, arms, and weapons of the WDO Yamantaka, as well as other such deities (Linrothe, 1999, pp. 188, 268-269 and 279-280, for example). Third, he serves as a destroyer of obstacles (Skt: vighnantaka). By vanquishing the various monsters, spirits, and fallen stars that threaten the life of his master Tripitaka, Sun clears the path of manifested demons that obstruct the monk’s path to enlightenment. Thanks to his help Tripitaka becomes an enlightened Buddha at the end of the novel (Wu & Yu (Vol. 4), 2012, p. 381). Fourth, Sun serves as the guardian and strong-arm of a Bodhisattva, per phase one of the recognized WDO iconography. Tripitaka is after all the Golden Cicada Bodhisattva reborn on earth. Fifth, Monkey is so powerful that he poses a threat to the August Jade Emperor of Heaven, just like the WDO Trailokyavijaya did for the supreme deva Mahesvara. This ultimately explains why the celestial army is no match for Sun and why other guardian deities, like the Heavenly Kings, fear and respect him.  Identifying the Great Sage as a Wrathful Destroyer of Obstacles helps locate his position in the novel’s Buddhist pantheon prior to his elevation to Buddhahood. This means Monkey is no longer the Buddho-Daoist “wild card” that doesn’t really seem to fit in anywhere.
The author/compiler of Journey to the West would have had plenty of esoteric material to influence his depiction of Monkey. Esoteric Buddhism filtered into China by the early Tang Dynasty (618-907) and continued into the Song (960-1279) thanks to royal patronage. People of the neighboring foreign Khitan Liao (907-1125), Tangut Western Xia (1038-1227), and Jurchen Jin (1115–1234) dynasties, all of whom conquered northern China at one time or another, adopted the religion. The Mongols, another foreign ruler of the Middle Kingdom, were great adherents of Vajrayana Buddhism during the Yuan Dynasty (1271–1368), which ensured the continued presence of esoteric imagery in China. And during the Ming (1368-1644), when Journey to the West was first published, the Yongle (r. 1402-1424) and Zhengde (r. 1505-1521) emperors, as well as other elite members of society, patronized and/or practiced the religion (Stoddard, 2008; Orzech, Sorensen, & Payne, 2011).
1) The krodha-vighnantaka term was coined by Rob Linrothe (1999) since the names traditionally given to said wrathful deities over the centuries are not appropriate to cover all three historical phases of their existence (pp. 19-20).
2) The first artists to represent WDOs drew on previous depictions of semi-divine Yaksa spirits, the dwarf-like Gana attendants of Shiva, and the humanoid personification of divine Hindu weapons (Skt: ayudhapurusa) (Linrothe, 1999, pp. 12-13).
3) The three poisons are stupidity, greed/lust, and anger. These are often depicted in the center of Buddhist Wheel of Life art as a boar, a snake, and a rooster, each biting the others tail, forming a circle.
4) Rob Linrothe (1999) writes that Shiva in this case represents the conquering of ego instead of “a Hinduism which must be humiliated” (p. 26).
5) During the Great Sage’s rebellion, the August Jade Emperor is forced to ask the Buddha to intervene because Sun Wukong is too strong (Wu and Yu (Vol. 1), 2012, p. 191-192). Monkey defeats the celestial army, along with the Heavenly Kings, prior to being subdued (Wu and Yu (Vol. 1), 2012, p. 172). And later the guardians “ben[d] low to bow to him and dare not bar his way” when he visits heaven some centuries after his rebellion (Wu and Yu (Vol. 4), 2012, p. 118).
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Linrothe, R. N. (1999). Ruthless compassion: wrathful deities in early Indo-Tibetan esoteric Buddhist art. Boston, Mass: Shambhala.
Orzech, C. D., Sorensen, H. H., & Payne, R. K. (2011). Esoteric Buddhism and the tantras in East Asia. Leiden: Brill.
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