妙法蓮華經玄贊 4.58

4.58

Because their vows differ. Both are turbid worlds, and both transform the three vehicles, employing the provisional first and the real later, and both are transformation bodies. If among all reward buddhas and transformation buddhas they do not transform the two vehicles and use the provisional first and the real later, it is not necessarily in a turbid time that the buddha appears in the world. If they transform the two vehicles, using the provisional first and the real later, they must appear in a turbid time, so that those of evil birth who are difficult to transform may gradually enter the path. What is here called "turbid" means that as one enters the decreasing kalpa and these five gradually arise, it is called a turbid time. Thus Maitreya Buddha only appears in the world at the beginning of the decrease from eighty thousand years as it gradually tends toward the five turbidities; it is not necessary that human lifespan reach twenty or thirty years when the minor disasters arise for it to be called the turbidity of the kalpa. Hence the treatises say: "When the kalpa decreases, buddhas arise in the world; when the kalpa increases, wheel-turning kings appear."