法華玄論 9.47

9.47

Answer: Speaking in terms of events: gathering once and transforming once would leave people obscured and unaware that the lands are vast and the buddhas are numerous; now, to make them realize that the buddhas are numerous and the lands are vast, he gathered three times and transformed three times. Furthermore, all buddhas frequently employ threefold matters, such as the three testings and the like. In terms of what is signified: because when the mind is defiled the land is impure, and when the mind is pure the land is pure, the mental defilements of sentient beings of the three faculties ought to be purified, hence the lands are transformed three times.