大般涅槃經集解 66.56

66.56

案僧亮曰：善不善者，類三界煩惱說不善也。寶亮曰：善是緣因，不善是境界因也。六住雖有無色界細惑，為苦用輕，不甚迫心，故不與境界名也。

Sengliang states: "'Good and ungood' refers to classifying the afflictions of the three realms as ungood." Baoliang states: "The good is the contributory cause; the ungood is the objective-domain cause. Although the sixth abiding possesses subtle delusions of the formless realm, their painful function is light and does not severely oppress the mind, so it is not given the name of an objective domain."