Shùbó-jiā 戌博迦 was a crown prince. He did not really want to become the king of his small state. Instead, he wanted to leave the world of red dust and follow the Buddha and find enlightenment. But he knew he had responsibilities to his kingdom.
His younger brother, however, wanted very much to become king, and was prepared to mount an armed rebellion against Shùbó-jiā in order to claim the throne.
And so, to calm his brother and to prevent a war, and above all to pursue the path he had decided he must follow to find enlightenment, he called his brother to him, and explained that there was no desire in his heart to rule the land. All that was in his heart was the buddha nature.
His brother did not believe any of this. Whatever the buddha nature might be, it could not compare with the joy of running a kingdom, even a little kingdom and having everyone obey one’s every command and cater to one’s every whim. And so his brother suspected that Shùbó-jiā was merely trying to fool him with some unworthy ruse.
Shùbó-ja protested that he was completely sincere. And with that, he pulled open his gown, and the face of a buddha was seen peering out from the middle of his chest, for indeed in his heart there was only the buddha nature.
So that is how he is represented in art today. And it is why he is called “The Arhat Who Bares His Heart.”