佛說觀佛三昧海經 4.9

4.9

The Buddha told Ānanda: "The light of the Tathāgata's mark of the white curl has already been broadly expounded by the Buddhas in the sūtras. Such wondrous light is seen only by Buddha and Buddha; even bodhisattvas of the ten grounds do not see it clearly. Therefore, here it is spoken of only in small part; speaking of a small part is done for ordinary mortals. After the Buddha's parinirvāṇa, one who contemplates like this engages in right contemplation; if one contemplates otherwise, it is called wrong contemplation. This light eliminates sins as explained above. Only those who see the light attain clarity of mind and see a hundred billion Buddhas; seeing the white hair itself is a vision formed by mental conceptualization.