Mount Wutai is well-known as an important site in Chinese Buddhism, and Tan-luan (Donran) climbed it at the age of fifteen. At that time, he was struck by the mountain's mystical atmosphere and made up his mind to become a priest. Learning in lectures of the Four Treatise School of Buddhism was standard of the time, so Tan-luan learned in the sect as well. He also undertook thorough studies of the profound and extensive Sutra of the Great Assembly. However, he worked so ardently and incessantly on his studies that it took a toll on his body, and he ended up suffering from a grave illness. Fortunately, he escaped the jaws of death and recuperated in his hometown. Then, he asked himself, “Now I come to think of it, life is fragile and could be over at any moment. How can I master a teaching as vast as Buddhism in such a fleeting life? Shouldn’t I seek perpetual youth and longevity first so that I actually can read all the sutras and thoroughly realize the true intention of Shakyamuni Buddha?”
He decided to go to Jiangnan and visit Tao Hong-jing, who was said to have attained the secret of immortality. Tan-luan’s ardent study was well recognized by Tao Hong-jing, and he was bestowed 10 books on the secrets of immortality. Delighted, Tan-luan left Tao Hong-jing’s place to head home. Passing through Luoyang on the way, he came across Bodhiruci (Sanzorushi), who was a pre-eminent Buddhist translator. Tan-luan proudly said to Bodhiruci, “These texts explain the way to achieve perpetual youth and longevity!” But Bodhiruci spat on the ground in disgust. “How disgraceful!”
When Tan-luan indignantly asked Bodhiruci why he said this, Bodhiruci replied, “In this fleeting world where all is impermanent, how can you expect to find the secret to immortality? Even though you may achieve longevity, there is no way to escape death. Once you die, you will go to the next world. Is this not the most crucial of all matters? In spite of the fact that you were learning the Buddhist teachings, you have allowed yourself to be led astray by these Taoist teachings. It is completely and utterly unthinkable."
Yet Tan-luan did not back down. He argued, “How can we master Buddhism with our limited lifespan? Is there any secret of longevity in Buddhism better than what's taught in these Taoist texts?” Bodhiruci smiled. “There is, there is!” he said, and he showed Tan-luan the Sutra of Contemplation on the Buddha of Infinite Life. “Please look at this sutra. This teaches the way to attain longevity and immortality. It is the teaching that allows you to be granted unlimited life by Amida Buddha!"
Tan-luan read the Sutra of Contemplation on the Buddha of Infinite Life for the first time and was suddenly struck by the greatness of this sutra.
Awakened from his delusion, Tan-luan burned all ten volumes of the Taoist scripture he had so painstakingly earned right in front of Bodhiruci and took refuge in Pure Land Buddhism. From then on, Tan-luan dedicated his life to conveying Amida Buddha's Vow.