Thus have I heard. At one time the Buddha was staying in Śrāvastī at the Jeta Grove, in Anathapiṇḍada’s Park.

Then the Exalted One said to the bhikṣus: There are these two persons who indulge in slandering the Tathāgata. Which two? He who claims as the Tathagata’s teachings what is not his teaching, and he who claims as unauthentic teaching what is authentic teaching. Furthermore, there are these two persons who do not slander the Tathagata. Which are the two? He who declares unauthentic teaching as unauthentic teaching, and he who declares authentic teaching as authentic teaching. Therefore, bhikṣus, what is unauthentic teaching has to be declared as such, and what is authentic teaching also has to be declared as such. Thus bhikṣus, you should train.

Having heard the Buddha’s words, the bhikṣus were pleased….’