大方廣佛華嚴經疏 1.17

1.17

九開因性者，謂上因果理事，皆由眾生性有。若性非金玉，雖琢不成寶器。良以眾生包性德而為體、依智海以為源，但相變體殊、情生智隔，今令知心合體、達本情亡，故談斯經以為顯示。亦有二種：一以言顯示令其知有；二使其修行悟入顯現，如下破塵出經卷等。亦如《法華》云「唯以一大事因緣故出現於世，所謂開示悟入佛之知見。」眾生等有，故言唯一。

Ninth, opening up the causal nature: the causes, fruits, noumenon, and phenomena above are all possessed by the nature of sentient beings. If the nature is not gold or jade, though carved, it will not become a precious vessel. For indeed, sentient beings take the virtue of the nature as their essence and rely on the ocean of wisdom as their source; yet marks shift and essences seem distinct, emotion arises and wisdom is estranged. Now, to let them know that the mind accords with the essence and to realize the source so that emotion vanishes, this sūtra is spoken to reveal it. This also has two kinds: first, revealing it through words to let them know it exists; second, causing them to cultivate and realize it so that it becomes manifest, like cracking the paramāṇu to bring forth the sūtra scroll below, and so forth. It is also as the Saddharmapuṇḍarīka says: 'It is only for the causes and conditions of one great matter that they appear in the world, namely to open, reveal, awaken to, and enter the vision and knowledge of the Buddha.' Because sentient beings possess it equally, it is said to be 'only one.'