大般涅槃經集解 13.56

13.56

明駿案：廣二者恒也。常以不遷無動嶷然為義，恒以亘然不改為義，亦左右之辭耳。所以未舉虛空無際無跡，蓋言終曰恒然者也。

Mingjun notes: This expands on the second, constancy. Permanence takes non-transmutation, immobility, and steadfastness as its meaning; constancy takes perpetual changelessness as its meaning; they are also just complementary terms. The reason it has not yet adduced empty space being boundless and traceless is presumably to speak of that which is constantly so throughout.