Self-protection was a human need for survival, an instinct.
When an object came hurtling toward someone, they would instinctively raise their hands to block it. That arose from the mechanism of self-protection.
When Sun Wukong wreaked havoc in the Heavenly Palace, he had not been thinking of protecting himself. This kind of "protection" did not mean using his Golden Cudgel to knock away the weapons attacking him.
The immortals living in the Heavenly Palace did not have a precept against killing that they were required to observe, like the Buddha did. They simply lacked the ability to capture the "Protector of the Heavenly Stables."
Yet the Great Sun Tathagata, who had the ability to suppress Sun Wukong beneath Five-Finger Mountain, had to abide by the precept against killing. Thus, after causing such tremendous havoc, the "Monkey King," whom everyone wished to get rid of, was not punished like Zhu Bajie and Sha Wujing for some minor offense and sent back into the cycle of reincarnation as a demon.
In the later story, everyone in the Heavenly Palace addressed Sun Wukong as "Great Sage," and "Sun Wukong" was no longer as lawless as he had been when he wreaked havoc in the Heavenly Palace, Dragon King's Palace, and the underworld. Even so, apart from the Western Paradise, the Monkey King could not possibly obtain another official post anywhere else.
Third Prince Nezha had not understood before, either. He acted as he pleased and tore out the dragon tendons. The Dragon Kings could do nothing to him, but they could make life difficult for the common people. So his father decided to sacrifice him to quell the Dragon Kings' fury.
Sun Wukong was a stone monkey, with no father or mother and no one to restrain him. The monkeys of Flower-Fruit Mountain,