俱舍論記 5.54

5.54

「此同前定至善等起故」者，此滅盡定同前無想定，性唯是善，非無記、染，四種善中等起善故。又染、無記非寂靜故。

"This, like the preceding attainment, [...] because of being arisen from wholesome [motivation]": this attainment of cessation, like the preceding attainment devoid of ideation, is purely wholesome in nature, neither non-defined (avyākṛta) nor defiled (kliṣṭa), because among the four kinds of wholesomeness it is wholesome by origination (samutthāna-kuśala). Furthermore, the defiled and non-defined are not tranquil.