A long time ago, there was a king in India with a very violent temperament. One day, this king went out hunting and was chasing a deer, but he lost sight of it.
The king saw a monk sitting in zazen under the shade of a tree, so he asked the monk where the deer had gone. However, as a monk, he could not lie, so he remained silent. The quick-tempered king became enraged and, without warning, cut the monk's arm.
To everyone's amazement, instead of blood, something white and milk-like flowed from the deep wound.
The king’s retainers were shocked and exclaimed, "Your Majesty, please stop! This is a noble monk who strictly follows the precepts." The monk, enduring the pain, spoke calmly. "Every action in this world will bring its due reward, either in this life or the next. Being cut by you is perhaps a result of past karma or a test in this life. I bear no hatred towards you, for Buddha teaches us to hold compassion for all people and living things. The fact that my blood has turned white like a mother’s milk is likely because of this teaching. How unfortunate it is that Your Majesty, unaware of this teaching, resorts to violence."
Humbled by the monk's attitude, the king was filled with fear and sincerely begged for forgiveness. The monk smiled gently and said, "If you truly repent with a pure heart, even heavy sins will become lighter."
The king solemnly vowed never to act violently again.
(From the Rokudo-shu Sutra)
When Buddhism was transmitted from India to China, there were life-threatening dangers, and spreading the teachings was extremely difficult. It could not have been accomplished without a strong wish and the strength of character.