Sāmaññaphalasutta (The Fruits of the Ascetic Life sutra)

This text is part of the Pali Canon (p. Tipitaka), from the basket of sermons or sutras (p. Suttapitaka); it is the second of the 34 sutras that make up the long discourses (Dīgha Nikāya). 

It offers a portrait of Buddhist discipline with examples, showing how the Buddha adapted his teachings to the ability of his listeners to understand. 

The narrative begins with the king of Magadha, Ajātasattu, son of King Bimbisāra, one of the Buddha’s first followers. After visiting six famous masters, he goes to the Buddha in search of serenity. He asks him whether the fruits of the ascetic and wandering life are visible in this world, akin to benefits yielded by the various trades. The Buddha answers him first with questions and, then, explains his doctrine through the example of a man who leaves his home out of faith in it and the stages he goes through before attaining the final liberation. After listening to this, Ajātasattu asks Buddha to accept him in the Buddhist community as a lay devotee and confesses that he killed his father to ascend to the throne. Buddha accepts his confession as progress in the discipline.