成唯識論演祕 5.246

5.246

顯平等三別之所以。故《雜集》第一云：心平等性者，謂以初中後位辨捨差別，所以者何？由捨與心相應離沈沒等，不平等性故，最初證得心平等性，由心平等遠離加行，自然相續故。次復證得心正直性，由心正直，於諸雜染無怯慮故，最後證得心無功用住性。

This reveals the reason for the distinctions among the three kinds of equality. Therefore the first fascicle of the Abhidharmasamuccaya-vyākhyā says: mental equality means distinguishing the distinctions of equanimity in the initial, middle, and subsequent stages. Why is this? Because when equanimity is associated with the mind, it departs from sinking and so forth, which are forms of inequality, and thus initially one realizes mental equality; because of mental equality, one departs from effort, and it flows spontaneously in succession; next, one further realizes mental uprightness; because of mental uprightness, one has no timidity or apprehension regarding defilements; finally, one realizes the nature of the mind abiding without exertion.