維摩經玄疏 5.7

5.7

Third, clarifying that sūtra contains the sense of "bubbling spring": this illuminates the meaning by way of a metaphor, like a spring bubbling and flowing, surging without exhaustion. The Buddha uses the four siddhāntas to preach the Dharma, with inexhaustible text and meaning, the flow of Dharma never ceasing, moistening the sprouts so that the three grasses and two trees, born of the one earth, all attain growth. Therefore sūtra contains the sense of "bubbling spring".