金剛經纂要刊定記 1.76

1.76

潛通血脈者。潛謂潛闇，通謂通流，血脈者喻也。以經中多分唯有能斷之語而無所斷之言，由是文起孤然勢意斷絕，及尋經旨皆有所因，文雖不彰理且連貫，以不明顯故曰潛通。其猶人身血脈，外雖不彰內宛流注，約喻顯法，故曰潛通血脈也。此意見於逐叚敘疑之文。

"Latently connects the bloodlines": "Latently" means hidden and obscured; "connects" means flowing through; "bloodlines" is a metaphor. Because the sūtra for the most part only contains words that sever [doubts] without containing words for what is severed, the arising of the text appears isolated and its momentum and sense seem broken; yet upon investigating the sūtra's purport, each has its reason. Though the text is not obvious, the principle is nevertheless coherent; because it is not manifest, it is called "latently connects." It is like the bloodlines of the human body: though outwardly not manifest, inwardly they flow smoothly. Applying the metaphor to reveal the Dharma, it is therefore called "latently connects the bloodlines." This meaning appears in the texts introducing the doubts section by section.