The deity often depicted with a blue body and a vajra scepter, and regarded as the protector of the Buddha’s teachings, is Vajrapani.
Vajrapani’s Sanskrit name means “Holder of the Vajra,” referring to the thunderbolt-like ritual weapon associated with indestructible power. In Mahayana Buddhism, he is one of the earliest bodhisattvas and serves as both protector and guide of Gautama Buddha.
Buddhist tradition often presents Vajrapani alongside Manjushri and Avalokiteshvara. The three embody essential qualities of Buddhahood: Vajrapani represents power, Manjushri wisdom, and Avalokiteshvara compassion. His fierce appearance is therefore protective rather than evil; wrathful imagery symbolizes the force used to overcome obstacles and hostile forces.
A common mix-up is confusing Vajrapani with Mahakala or other blue dharmapalas. Vajrapani is especially identified by the vajra held in his hand and by his role as the embodiment of enlightened power. In Tibetan Buddhism he is known as Chakna Dorje, “the Vajra in Hand.”