The Ruyi Jingu Bang is Sun Wukong’s signature weapon and one of the most recognizable magical arms in Journey to the West.
After mastering his supernatural abilities and returning to Flower-Fruit Mountain, Sun Wukong finds ordinary weapons far too light for his strength. He is told that the Dragon Palace of the Eastern Sea contains many treasures, so he descends beneath the waves and demands a weapon worthy of him from Ao Guang.
The Dragon King has various weapons brought out, but Sun Wukong dismisses them one after another as too light. Eventually his attention is drawn to an enormous iron pillar deep within the palace, shining with supernatural light.
The pillar is the divine iron once associated with Yu the Great’s control of the waters. It weighs thirteen thousand five hundred jin and stands in the sea as something far beyond an ordinary weapon.
When Sun Wukong approaches it, the iron seems almost destined for him. He wishes that it were shorter, and it shrinks. He wishes that it were thinner, and it changes again. At last it becomes a staff perfectly suited to his hand, bearing the name Ruyi Jingu Bang and its tremendous weight.
From that moment onward, the divine iron becomes inseparable from the Monkey King.
Its defining power is contained in the word ruyi: it responds to its owner’s will. In battle it can grow to enormous size, while at rest it can shrink as small as an embroidery needle, allowing Sun Wukong to hide it inside his ear.
During Havoc in Heaven, Sun Wukong swings the staff against celestial armies. During the pilgrimage, it accompanies him through battle after battle against demons, monsters, and supernatural enemies.
Even the great staff is not invincible. Taishang Laojun’s Vajra Cutter is capable of seizing it, leaving Sun Wukong without the weapon upon which he normally relies.
The Ruyi Jingu Bang became legendary not simply because of its immense weight or its ability to change size, but because it is almost impossible to separate the weapon from the image of Sun Wukong himself. When the Monkey King appears, the iron staff drawn from his ear and expanding in his hand is rarely far behind.
