觀無量壽佛經疏 4.43

4.43

五、從此紫金臺已下，正明第十門中到彼華開時節不同。由行強故上上即得金剛臺，由行劣故上中即得紫金臺，生在寶池逕宿如開也。

Fifth, from 'this purple-gold pedestal' downwards, directly clarifies in the tenth gate the different timings of the flower opening upon arrival. Because their practice was strong, those of the highest of the high obtain a vajra pedestal; because their practice was lesser, those of the middle of the high obtain a purple-gold pedestal, and being born in the jeweled pond, after passing a night it opens.