Following the Buddha's teachings  The Buddha spoke the Four Noble Truths and many other teachings, but at the heart they all stress the same thing. An ancient story explains this well. Once a very old king went to see an old hermit who lived in a bird's nest in the top of a tree, "What is the most important Buddhist teaching?" The hermit answered, "Do no evil, do only good. Purify your heart." The king had expected to hear a very long explanation. He protested, "But even a five-year old child can understand that!" "Yes," replied the wise sage, "but even an 80-year-old man cannot do it."