Cutting Off Doubt as Taught in the Laṅkāvatāra Sūtra

Original text: 大慧。疑相者。谓得法善见相故。及先二种身见妄想断故。疑法不生。不于余处起大师见。为净不净。是名疑相。须陀洹断。

Explanation: The Buddha said, "Mahāmati, the characteristic of doubt refers to the mental state of having attained truthful insight into the Dharma, of knowing well the characteristics of the Dharma, and of knowing whether the Dharma accords with reason or not; and because the delusive constructions of the two aforementioned kinds of identity view—the innate identity view and the imputed identity view—have been severed, doubt about the Dharma no longer arises, and one no longer doubts whether the Dharma accords with reason or not. Because doubt has been eliminated from the mind, one no longer seeks evidence elsewhere to prove whether one's view is pure or impure, or whether one has attained purity of the Dharma eye or not. Having such lingering doubt is the characteristic of doubt; it has already been severed by those at the first fruit of stream-entry (Srotaāpanna)."