大方廣佛華嚴經隨疏演義鈔 69.23

69.23

疏「然準瑜伽」下，後揀濫，濫前三句故。前三句者，即第四後際實，第五先際，第六盡實。正約眾生當中際故，故今釋云：此明三世約時辨異，今此約位以明三際。前際即七地已前，後際即九地已後，中際即當八地。雖約位有殊，而體無增減。又前三先際唯染，後際唯淨，中自約生；今之三際皆通染淨，又不同也，故疏結云「論就染淨明之」。

Regarding the commentary's "However, according to the Yogācāra..." and below: this later part eliminates confusion, because it might be confused with the previous three phrases. The previous three phrases are the fourth, the future boundary actuality; the fifth, the past boundary; and the sixth, the exhaustion actuality. Because they directly take sentient beings as corresponding to the middle boundary, it is now explained: that previous passage explained the three periods of time to differentiate according to temporal eras, whereas this passage explains the three boundaries according to stages. The past boundary is prior to the seventh stage; the future boundary is subsequent to the ninth stage; and the middle boundary corresponds to the eighth stage. Although there are differences according to stage, the essence is without increase or decrease. Furthermore, among the previous three, the past boundary is exclusively defiled, the future boundary is exclusively pure, and the middle boundary is itself treated in terms of sentient beings; the present three boundaries all encompass defilement and purity, which is also different; hence the commentary concludes, "The treatise explains it with respect to defilement and purity."