觀無量壽佛經疏 3.23

3.23

「又細想及麁想，心水即動，心水既動，靜境即失。又細塵及以麁塵投之寂靜水中，其水波浪即動。又行者等但看此水動不動相，即識自心住不住也。又境現失不失、邪正等，一同前日觀也。又天親讚云：『觀彼世界相，勝過三界道，究竟如虛空，廣大無邊際。』此即總明彼國地之分量也。」

"Furthermore, with subtle thoughts and coarse thoughts, the water of the mind stirs; once the water of the mind stirs, the tranquil object is lost. Likewise, when fine dust and coarse dust are dropped into quiet water, its ripples stir. Practitioners need only observe whether this water is moving or not moving, and they will recognize whether their own minds are resting or not resting. Furthermore, whether the object manifests or is lost, and whether it is false or correct, are entirely the same as in the sun contemplation above. Also, Vasubandhu's praise says: 'Contemplating the marks of that world, / It surpasses the pathways of the triple realm; / Ultimately like empty space, / Vast and without boundary.' This generally clarifies the measure of the ground of that land."