Tao-sheng Commentary on the Lotus Sutra, p275-276Thereupon a stupa of the seven treasures sprang up from underground and hung in the sky before the Buddha.
The purpose of manifesting the stūpa is to verify that the li underlying the Dharma Blossom is certainly clear and proper, first, through the evidence of the stūpa and, second, through the evidence of the voice that issues forth therefrom. Through the two events, beings come to bear faith to a full and deep extent. By extension it also shows that the ultimate fruit is subtly manifested, as it is ever existent.
Man’s emotions [tend to make him] dark about li. [The Buddha] cannot help but cause him to nurture faith by resorting to supernatural wonders. In an attempt to manifest and prove [his preaching] through this method, [the Buddha] shows the jeweled stūpa. Through this event he reveals his meaning, making it manifest and visible. It already was said that the three vehicles are the One. All living beings are [potentially] Buddhas and also are all in nirvāṇa. Nirvāṇa and Buddhas are set apart by as little as [the difference] between beginning and end. Also why should there be any difference [between beings and Buddhas]? Only because of the instigators of depravities is [Buddha-nature] concealed, like a stūpa lying hidden, sometimes underground, covered by earth. The endowment of great enlightenment cannot be left covered up. It is bound to be drawn out in due course, like the stūpa issuing forth. It cannot be stopped from coming out. It originally was existent in empty li, like the stūpa resting in midair. The sound of the voice issuing [from inside the stūpa], praising with the words, “How excellent! How excellent!” expresses a final affirmation. The words set about with sundry precious objects implicitly show that the ultimate fruit encompasses all kinds of good. Thus, its li becomes manifest by way of the event [conjured up by the Buddha]. Though it is difficult and unbelievable, it can be obtained.