大般涅槃經義記 4.222

4.222

第四句中，「是人思」等，釋有二義：一對上初義，約就凡夫二乘以解，凡夫二乘久後思量，知由諸聖顯性行同，故令性一，如人思量犢子眾生感乳業同，故令乳一；二對上後義，約就修行菩薩以釋，修行菩薩久思由聖顯性行同，故令性一。

In the fourth line, "this person thought," etc., has two meanings in explanation: first, corresponding to the first meaning above, it is explained in terms of ordinary persons and those of the two vehicles: ordinary persons and those of the two vehicles, thinking it over after a long time, know that because the noble ones reveal that the practice of the nature is the same, it makes the nature one, just as a person considers that the calves and sentient beings share the same karma for drawing milk, which makes the milk one; second, corresponding to the latter meaning above, it is explained in terms of the practicing bodhisattva: the practicing bodhisattva, considering for a long time that the noble ones reveal that the practice of the nature is the same, knows that it makes the nature one.