大般涅槃經集解 48.36

48.36

案。僧亮曰觀愛貪，合第三譬也。見不見聞不聞，至後還不見者，入觀則了，出觀則生惑。二乘亦爾，本為向初果為譬，因說愛之難除耳。

Sengliang comments: Contemplating craving and greed matches the third metaphor. Seeing and not seeing, hearing and not hearing, down to later again not seeing: when entering contemplation one is clear, but when emerging from contemplation delusion arises. The two vehicles are also like this. Originally it served as a metaphor for proceeding toward the first fruit, and by occasion spoke of craving being difficult to eradicate.