八識規矩補註 2.17

2.17

謂此識於初地初心既轉成無漏，則相應心品轉智亦成無漏，由第六識入雙空觀故。謂第六入生空觀故，礙此第七我執不生，法執猶恒，故《論》云：「單執末那居種位，平等性智不現前。」謂由第六入生、法二空觀故，礙此第七我、法二執不起，故《論》云：「雙執末那歸種位，平等性智方現前。」謂第七識無力斷惑與執，全仗第六識也。故頌云：「分別二障極喜無，六七俱生地地除，第七修道除種現，金剛道後總皆無。」故第七成於無漏，皆由第六以斷惑證理勝故。

This means that when this consciousness transforms into the uncontaminated at the initial heart of the first bhūmi, the wisdom into which the corresponding mental factors are transformed also becomes uncontaminated, because the sixth consciousness enters the contemplation of dual emptiness. When the sixth enters the contemplation of the emptiness of persons, it hinders this seventh's ātmagrāha from arising, but dharmagrāha remains constant; hence the Treatise says: "When manas with only singular grasping abides in the seed state, the wisdom of equality does not manifest." When the sixth enters the contemplation of both emptinesses of persons and dharmas, it hinders this seventh's two grasps of self and dharmas from arising; hence the Treatise says: "When manas with dual grasping returns to the seed state, the wisdom of equality only then manifests." This means that the seventh consciousness lacks the power to sever afflictions and grasping, relying entirely on the sixth consciousness. Hence a verse says: "The differentiated two hindrances are absent at the Utmost Joy; the innate [hindrances] of the sixth and seventh are eliminated bhūmi by bhūmi; the seventh on the path of cultivation eliminates seeds and manifestations; after the vajra-path, all are completely absent." Therefore, the seventh becoming uncontaminated is entirely due to the superiority of the sixth in severing afflictions and realizing the principle.