大毘盧遮那經供養次第法疏 2.49

2.49

In the ninth section, the mantra gate of Śākyamuni Tathāgata: next, Śākyamuni Tathāgata enters the jewel-locus samādhi; jewels emerge from it, so it is called jewel-locus. It is like the great ocean producing various jewels: if one arrives at that island, then whatever one wishes and requires is lacking in nothing. After the Buddha enters this samādhi, from the gate of his face emerge various lights, and in the lights this mantra appears, up to pervading all Buddha-kṣetras. One should know that the other mantras are all spoken like this.