維摩經略疏 9.72

9.72

「德頂」者，聲聞法中為頂禪，於諸禪中最上。今明此菩薩若無中道之德則有頂墮，有中道德故則無頂墮，無順道之愛故稱德頂。「垢淨為二」者，若欲界苦集為垢，非想定離下地為淨。如三界見思為垢，二乘斷三界垢為淨。淨不可為垢、垢不可為淨，是故為二。今觀此垢實性猶若虛空，虛空之相無垢無淨，一切法皆如相寂滅者，即順寂滅也。既垢淨為二，不順不滅。今不見垢淨，雙亡兩邊，得入中道。

'Guṇaśikhara' (Virtue-Summit): in the Śrāvaka Dharma it is the summit dhyāna (mūrdhadhyāna), the highest among all dhyānas. Now it is clarified that if this bodhisattva lacked the virtue of the Middle Way, there would be a fall from the summit; because he possesses the virtue of the Middle Way, there is no fall from the summit. Because he lacks craving for conforming to the Path, he is called Guṇaśikhara.
'Defilement and purity are dual': if the suffering and origination of the desire realm are defilement, the realm of neither-perception-nor-non-perception leaving behind the lower grounds is purity. Just as the views and thoughts of the three realms are defilement, the two vehicles severing the defilements of the three realms is purity. Purity cannot be defilement, and defilement cannot be purity; therefore they are dual. Now, contemplating the true nature of this defilement as being like space: the mark of space has neither defilement nor purity. When all dharmas are quiescently extinguished according to their suchness, this conforms to quiescent extinction. Since defilement and purity are dual, they do not conform to non-extinction. Now, not seeing defilement or purity, both extremes are doubly eradicated, and one attains entry into the Middle Way.