One Pillar Gate
The Road to Bulguksa
Before becoming a Buddha, Prince Siddhartha practiced asceticism for six years in order to attain enlightenment. For these six years he sat continuously in meditation, neither eating nor bathing. Suddenly, however, one day he arose, went to the river, bathed himself, and drank a jug of milk offered to him by a young woman. Witnessing this spectacle and thinking that Siddhartha had been unable to withstand the rigors of asceticism any longer, five others who had been meditating with him left and went to continue their practice in the deer park. Now Siddhartha was left alone to meditate under the bo tree.
That night, Siddhartha realized the Truth and became a Buddha. Wanting to teach all who suffer about the way to enlightenment, he went first to the deer park where those with whom he had meditated were.
Seeing Siddhartha coming, the five ascetics made a promise to one another not even to greet the one who had proven so weak. But when Siddhartha came close, they all rose and greeted him. Siddhartha asked why they had greeted him, since they had promised one another not to. In response, the five ascetics could merely scratch their heads. "It is because I have become a Buddha," Siddhartha said, but the five did not believe him.
Buddha teaches that the way to awaken to the Truth lies neither in luxury nor in asceticism but in between them. One must not incline to either side but rather travel the middle way. This was Buddha's first sermon.
Standing for the one-mindedness that one must have as one enters the temple, the Iljumun or One Pillar Gate must stand perfectly straight, because if it leans just a little bit in either direction it is likely to fall over. This gate that must stand perfectly straight indicates the middle way that those who enter must follow.