俱舍論頌疏論本 25.26

25.26

無漏者，明練根道唯無漏性，以增上故。依人三者，依身門也，唯人三洲能修練根，天趣中無，謂無退故。

'Untainted' explains that the path of refining faculties is exclusively of an untainted nature, because it is predominant. 'Rely on the three [continents] of humans' refers to the bodily support: only humans in the three continents are able to cultivate the refinement of faculties; it does not exist among the heavenly destinies, because they do not fall away.