金光明最勝王經疏 4.203

4.203

由第三地由離闇鈍愚獲此總持，能發殊勝妙定三明，故如日圓。自離障云無垢，破他闇云相光。四地能離微細障故，精進殊勝，由如月輪初微至圓滿，能除已生未生之我見執，能生未生、能長已生一切善法故，如月光能作清涼，能開長蓮華。

The commentary says: Because on the third ground one is freed from the ignorance of dullness and obscurity, one obtains this dhāraṇī, which can give rise to superior, wondrous meditative absorption and the three knowledges; thus it is like the disk of the sun. Being freed oneself from obstacles is called "stainless"; destroying the darkness of others is called "the mark of light". Because on the fourth ground one can remove subtle obstacles, vigor is superior, just as the lunar disk proceeds from a slight crescent to fullness; because it can eliminate self-view and grasping, whether already arisen or not yet arisen, and can generate unarisen and augment arisen wholesome dharmas, it is like moonlight, which can produce cooling and open and expand lotus flowers.