四分律行事鈔資持記 1.289

1.289

邊地者。《伽論》止明邊不足中。本律捨戒互不成捨，故下約中國明之。必下，義決。本由言不相領而不足故。

Regarding the one from a borderland: the Mātṛkā merely clarifies borderland insufficiency. Under the root Vinaya, relinquishing the precepts reciprocally fails to constitute relinquishment; hence below it is explained in terms of the Central Country. From 'Must' onward, the meaning is determined. Fundamentally, it is because their words are not mutually understood that he is insufficient.