請觀音經疏闡義鈔 3.5

3.5

「五行」者，行天之氣也。老聃云：「天有五行，木、火、金、土、水，分時化育以成萬物。」「西即是金」者，東木、南火、西金、北水、中土。「若對四諦」者，謂東集、南苦、西道、北滅，故云即道諦也。「道是能通」等者，道是戒定慧，能破惑通至於理，如金能決斷也。「用智慧見理」者，此解道是能通義也。慧能見理，故是能通，理即所通也。

Regarding the "five elements" (wuxing): these are the circulating qi of heaven. Laozi said, "Heaven has five elements: wood, fire, metal, earth, and water; apportioning the seasons, they transform and nurture so as to bring about the myriad things." Regarding "the west is metal": the east is wood, the south is fire, the west is metal, the north is water, and the center is earth. Regarding "if correlated with the four noble truths": this means the east is the truth of accumulation, the south is suffering, the west is the path, and the north is cessation; hence it is said to be the truth of the path. Regarding "the path is that which can bring penetration" and so forth: the path consists of precepts, samādhi, and wisdom, which can shatter delusion and penetrate through to principle, just as metal can cut and decide. Regarding "using wisdom to see principle": this explains the meaning of "the path is that which can bring penetration." Wisdom can see principle, hence it is that which brings penetration, and principle is that which is penetrated.