金剛經纂要刊定記 2.217

2.217

皆一者，一義不同。謂：心境則泯之故一，理智則融之故一，凡聖則如之故一，本始則會之故一。義雖不同俱名為一，故云一時。

"Are all one": the meanings of 'one' are different. That is: mind and object are one through being extinguished; principle and cognition are one through blending; ordinary and noble are one through being as such; original and initial are one through uniting. Although the meanings are different, they are all termed 'one'; hence it is called 'at one time.'