The Great Sage caused havoc in Heaven, prompting the Jade Emperor to dispatch his celestial army. However, none could subdue him. Seizing the moment while the Monkey King was preoccupied with battling the God Erlang, Lord Lao Zi struck him on the head with his Diamond Jade Bracelet, capturing him at last.
The Jade Emperor ordered his execution, but sabers, axes, fire, and thunder failed to inflict a single wound. Lord Lao Zi then placed the Great Sage into the Eight Trigrams Furnace, used for refining elixirs, intending to burn him to ashes.
The furnace was structured around the eight trigrams. The Great Sage squeezed himself into the "Palace of Xun," associated with wind, reasoning that where there is wind, there can be no fire. He was spared the flames, though the smoke reddened his eyes.
After forty-nine days, Lord Lao Zi opened the furnace, believing the task complete. Instantly, the Great Sage leapt out with his As-You-Will Cudgel, knocked down the guards, and escaped. From that day forth, he possessed a pair of fiery eyes with golden pupils.