大毘盧遮那成佛經疏 3.46

3.46

The sūtra verse says: / "The practitioner's mind of compassion / Is aroused and made to expand; / When he firmly abides and receives instruction, / One should select level ground for him": / this says that when the ācārya has gained a disciple, next he explains the branch of preparing the ground. Here, the word "practitioner" in the Sanskrit text is "mantrin" (mantra practitioner); because six characters cannot fit in a verse, it was abbreviated according to the sense. There are quite a few such cases in the text below, which will not be explained repetitively. It means that the mantrin repeatedly arouses his mind with such wholesome dharmas, causing his aspiration to gradually expand. Knowing that he firmly abides, receives instruction, and will no longer waver, only then does he make the maṇḍala for him. Or, in yoga seeing that his capacity and conditions are already firm, only then does he select the ground. The great text of the Vajraśekhara and the Susiddhi and other sūtras extensively explain the characteristics of the ground; however, the general meaning is that this world is naturally not as completely level and upright as other pure realms, but according to the various superior places explained in the text below, selecting a level, upright, and dignified place where a circular altar can be made, one acts and performs without hindrance, and it can serve the purpose. Furthermore, creating altars anywhere is acceptable now; just as Vairocana's universally omnipresent, level ground of the mind only then makes the mahākaruṇā-maṇḍala, so wherever among the explained superior places there is a small portion that is level and can be purified, right therein one opens forth the maṇḍala of ten thousand virtues. The shallow and deep layers are in accordance with the extensive explanation given before.