The 139th Sutta of the Majjhima Nikāya. It was preached at Jetavana and contains a statement and an exposition of the middle path of peace between the two extremes of pleasures of sense - low, ignoble and unprofitable - and self-mortification, also painful and unprofitable. The path is the Noble Eightfold Path: in preaching the doctrine the preacher should neither appreciate nor depreciate it, he should teach the truth in abstract terms of general principle. He should not be a tale-teller nor confront anyone with improper remarks; he should speak slowly and not hurriedly; he should neither affect provincialisms in speech nor depart from recognised parlance.
At the end of the discourse a young man, Subhūti, is praised because he walked where calm dwelt (M.iii.230-7; MA.ii.977-8).