Kongosanmai-in, a special head temple of the Shingon sect on Mount Koya, was established in response to a petition by Hojo Masako, the wife of Kamakura Lord Minamoto Yoritomo, to commemorate Yoritomo's enlightenment. In the year Heisei 16, the entire region was designated as a UNESCO World Heritage site under the name "Sacred Sites and Pilgrimage Routes in the Kii Mountain Range," and among the sub-temples of Mount Koya, Kongosanmai-in is the only temple that holds this prestigious world heritage status.
The principal deity enshrined at the core of Kongosanmai-in's main hall is the statue of Aizen Myo-o (Ragaraja), a representation of Yoritomo's life-size meditating Buddha that he commissioned to be made by the sculptor Unkei. The statue's history is said to trace back to Yoritomo's time and it was relocated from Kamakura to Mount Koya when the temple was founded. Faithfully replicated using the sacred wood "hinoki," the embodiment of Yoritomo and Masako's bond, the Kongosanmai-in Aizen Myo-o statue symbolizes this connection. This statue has been consecrated within the main hall of Kongosanmai-in.
The Aizen Myo-o statue preserved within Kongosanmai-in is said to have been commissioned by either Hojo Masako upon Yoritomo's passing or by Yoritomo himself, and sculpted by Unkei. This statue bears witness to the strong connection between the temple and the Kamakura shogunate, and it exudes the significant influence of Unkei, who was residing in the eastern provinces during that era.
The once brilliant vermilion color of the statue, representing enduring devotion, has largely peeled off over time, exposing a deep black-brown hue that accentuates its fierce and wrathful expression. The intricately detailed craftsmanship, from the fiery halo representing the strong aspiration for enlightenment to the small jewels encircling the treasures on the pedestal, contributes to the statue's commanding presence.
Aizen Myo-o, who transforms human desires like afflictions and sensual cravings into the enlightened mind (bodhicitta), is attributed with this role. With the ability to connect various relationships, Aizen Myo-o has been widely venerated since the Kamakura period, not only for fulfilling romantic wishes but also for bestowing diverse blessings such as health, victory in battles, and more. The deity possesses a third eye that perceives all realms, wears a lion crown adorned with five-pronged vajras representing steadfast determination towards enlightenment, and sits in a lotus posture atop a vase filled with wisdom, showcasing enlightenment.