大般涅槃經疏 25.15

25.15

「師子吼」下，第四重明不退之行，先問、次答。通論六度皆是不退之行，今趣舉三十二相業，約求佛心便。上文明百福成一相；今文或一業成一相、或多業得多相；此就相似因果為語。一業一相、多業多相，示因果不差。佛實有四牙，而文但二牙者，二牙大、二牙白，兩白為一、兩大為一，故言二牙。又一解：若論牙則有四，若論邊則有二。今明二邊牙，故言二牙。

From "Siṃhanāda" onward, the fourth explains again the practice of non-retrogression, first asking, then answering. Speaking generally, the six pāramitās are all practices of non-retrogression; here it specifically adduces the karma of the thirty-two marks, because it is convenient for the mind seeking buddhahood. The text above explained that a hundred merits form one mark; the present text states that either one karmic action forms one mark, or multiple karmic actions attain multiple marks; this is spoken with regard to similar cause and effect. One karma, one mark; multiple karmas, multiple marks: this shows that cause and effect do not err. The Buddha actually possesses four canine teeth, yet the text only mentions two canine teeth: two canine teeth are large and two canine teeth are white; the two white are counted as one, and the two large are counted as one, hence it says "two canine teeth." Another explanation says: if speaking of the canine teeth, there are four; if speaking of the sides, there are two. Now it explains the teeth on the two sides, hence it says "two canine teeth."