After his awakening, the Buddha sat under this tree and pondered."Now I have found the Truth to end all suffering. How can I teach it so that other people can understand it and accept it? When I speak about the Truth, I might only confuse people or my message might go unheeded. Perhaps I should just pass on to nirvana."

Then there came the voice of Brahmadeva." No, please don't leave the world without teaching. You should propagate the Truth because so many people are suffering, both physically and mentally. Your teachings will save many of them." It is said that the deity entreated the Buddha three times, and only then did he finally agree to teach others what he had learned.

After making up his mind, the Buddha began to ponder whom he should teach first. He thought of his own two masters, but he soon learned that they had passed away. He then thought of those five ascetics he had practiced with before. When he learned that they were now at Mrgadava(also known as the Deer Park), he went to look for them.

When the five ascetics saw the Buddha approaching in the distance, they talked among themselves: "Look there, Siddhartha is coming. He abandoned asceticism and became a voracious glutton. When he arrives, let's not talk to him or even greet him." But when they beheld his majestic visage, they found that he was not the sort of person they had thought him to be. They were so astonished that they forgot what they had just been saying. Some of them quickly ran over and bowed, respectfully taking the robe and bowl from the Buddha's hands, while others prepared a cushion for him to sit on and rushed to get water to serve him.

After sitting down, the Buddha began to speak,"Bhiksus,I have attained the Truth of the universe, and I want to introduce and expound it to you. If you learn it and practice it according to my direction, you will soon be enlightened, not in the future, but in the present life or even in the present moment." The Buddha then began to teach these five monks about the Truth, and they became his first disciples. In Buddhism, this first lecture is called"the first turning of the Dharma Wheel."

The Buddha traveled along the Ganges River in northern India, lecturing wherever he went. The number of his disciples increased, so he organized the community of the monks(Sanskrit,"sangha"). It is said that he journeyed north as far as the city of Kailavastu, now Tilorakot in Tarai, Nepal. The southernmost point in his travels was Rajagrha, now at Rajgir in the middle section of the Ganges River. To the east, the Buddha went as far as Campa, now Bhagalpur, Bangladesh. To the west he reached Kausambi, whose exact location is not known-it may either be Kosam, a village by the Jumna River, or southwest of the city of Allahabad.

At that time, the caste system had been thoroughly developed in India. There were four castes: the Brahmans(or priests), rulers and warriors, merchants and commoners, and slaves. A person in a lower caste could not marry anyone in a higher caste, and the children in each caste inherited the same caste from their families. Thus a slave's descendants were always slaves-they could not become priests, warriors, or even commoners. The Buddha found the Hindu caste system repugnant, and he admitted anyone regardless of caste into the sangha, where all were treated impartially. He disregarded the background of anyone who came to him, either to become his disciple or to seek the dharma from him, and taught all equally.