金光明經文句記 2.199

2.199

初、壽。法性不變，無去來今，是真久義，約此久義釋法身壽。

First, the span of life. The Dharma-nature does not change and has no past, future, or present; this is the true meaning of permanence, and it is in terms of this meaning of permanence that the lifespan of the Dharma body is explained.