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Vajrapāṇi (from Sanskrit vajra, "thunderbolt" or "diamond" and pāṇi, lit. "in the hand") is one of the earliest bodhisattvas of Mahayana Buddhism. He is the protector and guide of the Buddha, and rose to symbolize the Buddha's power. Vajrapani was used extensively in Buddhist iconography as one of the three protective deities surrounding the Buddha. Each of them symbolizes one of the Buddha's virtues: Manjusri (the manifestation of all the Buddhas' wisdom), Avalokitesvara (the manifestation of all the Buddhas' compassion) and Vajrapani (the manifestation of all the Buddhas' power).
On the popular level, Vajrapani, Holder of the Thunderbolt Scepter (symbolizing the power of compassion), is the Bodhisattva who represents the power of all the Buddhas, just as Avalokitesvara represents their great compassion, Manjushri their wisdom, and Tara their miraculous deeds. For the yogi, Vajrapani is a means of accomplishing fierce determination and symbolizes unrelenting effectiveness in the conquest of negativity. His taut posture is the active warrior pose (pratayalidha), based on an archer's stance but resembling the en garde position in Western fencing. His outstretched right hand brandishes a vajra and his left hand deftly holds a lasso - with which he binds demons. He wears a skull crown with his hair standing on end. His expression is wrathful and he has a third eye. Around his neck is a serpent necklace and his loin cloth is made up of the skin of a tiger, whose head can be seen on his right knee.
According to the Pancavimsatisahasrika and Astasahasrika Prajnaparamita any Bodhisattva on the path to Buddhahood is eligible for Vajrapani's protection, making them invincible to any attacks "by either men or ghosts".
Vajrapāṇi is the patron saint of the Shaolin monastery.
In Japan, Vajrapani is known as Shukongōshin (執金剛神, "Diamond rod-wielding God"), and has been the inspiration for the Niō (仁王, lit. Benevolent kings), the wrath-filled and muscular guardian god of the Buddha, standing today at the entrance of many Buddhist temples under the appearance of frightening wrestler-like statues.