法華義疏 5.260

5.260

「周匝俱時」者，眾苦譬火，無處不有義同「周匝」。三界俱苦，說為「一時」。出於橫造，故云「欻然」也。「焚燒舍宅」者，煩惱為火燒心善根，眾苦為火焚身樂受也。

Regarding "all around at the same time": manifold sufferings are parabled by fire; there being no place where they are not present is equal in meaning to "all around." The three realms being all suffering is described as "at the same time." Arising unexpectedly, it is therefore called "suddenly." Regarding "burning the house": afflictions serve as the fire burning the wholesome roots of the mind; manifold sufferings serve as the fire burning the pleasant sensations of the body.